[ { "id": "authors:8vsxx-qwe90", "collection": "authors", "collection_id": "8vsxx-qwe90", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201027-153053132", "type": "article", "title": "Spitzer Reveals Evidence of Molecular Absorption in the Atmosphere of the Hot Neptune LTT 9779b", "author": [ { "family_name": "Dragomir", "given_name": "Diana", "orcid": "0000-0003-2313-467X", "clpid": "Dragomir-D" }, { "family_name": "Crossfield", "given_name": "Ian J. M.", "orcid": "0000-0002-1835-1891", "clpid": "Crossfield-I-J-M" }, { "family_name": "Benneke", "given_name": "Bj\u00f6rn", "orcid": "0000-0001-5578-1498", "clpid": "Benneke-B" }, { "family_name": "Wong", "given_name": "Ian", "orcid": "0000-0001-9665-8429", "clpid": "Wong-Ian" }, { "family_name": "Daylan", "given_name": "Tansu", "orcid": "0000-0002-6939-9211", "clpid": "Daylan-T" }, { "family_name": "D\u00edaz", "given_name": "Mat\u00edas", "orcid": "0000-0002-2100-3257", "clpid": "D\u00edaz-M" }, { "family_name": "Deming", "given_name": "Drake", "orcid": "0000-0001-5727-4094", "clpid": "Deming-D" }, { "family_name": "Molli\u00e8re", "given_name": "Paul", "orcid": "0000-0003-4096-7067", "clpid": "Molli\u00e8re-P" }, { "family_name": "Kreidberg", "given_name": "Laura", "orcid": "0000-0003-0514-1147", "clpid": "Kreidberg-L" }, { "family_name": "Jenkins", "given_name": "James S.", "orcid": "0000-0003-2733-8725", "clpid": "Jenkins-J-S" }, { "family_name": "Berardo", "given_name": "David", "orcid": "0000-0001-6298-412X", "clpid": "Berardo-D-A" }, { "family_name": "Christiansen", "given_name": "Jessie L.", "orcid": "0000-0002-8035-4778", "clpid": "Christiansen-J-L" }, { "family_name": "Dressing", "given_name": "Courtney D.", "orcid": "0000-0001-8189-0233", "clpid": "Dressing-C-D" }, { "family_name": "Gorjian", "given_name": "Varoujan", "orcid": "0000-0002-8990-2101", "clpid": "Gorjian-V" }, { "family_name": "Kane", "given_name": "Stephen R.", "orcid": "0000-0002-7084-0529", "clpid": "Kane-S-R" }, { "family_name": "Mikal-Evans", "given_name": "Thomas", "orcid": "0000-0001-5442-1300", "clpid": "Mikal-Evans-T" }, { "family_name": "Morales", "given_name": "Farisa Y.", "orcid": "0000-0001-9414-3851", "clpid": "Morales-F-Y" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "Ricker", "given_name": "George R.", "orcid": "0000-0003-2058-6662", "clpid": "Ricker-G-R" }, { "family_name": "Vanderspek", "given_name": "Roland", "orcid": "0000-0001-6763-6562", "clpid": "Vanderspek-R" }, { "family_name": "Seager", "given_name": "S.", "orcid": "0000-0002-6892-6948", "clpid": "Seager-S" }, { "family_name": "Winn", "given_name": "Joshua N.", "orcid": "0000-0002-4265-047X", "clpid": "Winn-J-N" }, { "family_name": "Jenkins", "given_name": "Jon M.", "orcid": "0000-0002-4715-9460", "clpid": "Jenkins-J-M" }, { "family_name": "Col\u00f3n", "given_name": "Knicole D.", "orcid": "0000-0001-8020-7121", "clpid": "Col\u00f3n-K-D" }, { "family_name": "Fong", "given_name": "Willie", "clpid": "Fong-Willie" }, { "family_name": "Guerrero", "given_name": "Natalia", "orcid": "0000-0002-5169-9427", "clpid": "Guerrero-N" }, { "family_name": "Hesse", "given_name": "Katharine", "orcid": "0000-0002-2135-9018", "clpid": "Hesse-K" }, { "family_name": "Osborn", "given_name": "Hugh P.", "orcid": "0000-0002-4047-4724", "clpid": "Osborn-H-P" }, { "family_name": "Rose", "given_name": "Mark E.", "orcid": "0000-0003-4724-745X", "clpid": "Rose-M-E" }, { "family_name": "Smith", "given_name": "Jeffrey C.", "orcid": "0000-0002-6148-7903", "clpid": "Smith-J-C" }, { "family_name": "Ting", "given_name": "Eric B.", "orcid": "0000-0002-8219-9505", "clpid": "Ting-Eric-B" } ], "abstract": "Non-rocky sub-Jovian exoplanets in high-irradiation environments are rare. LTT 9779b, also known as Transiting Exoplanet Survey Satellite (TESS) object of interest (TOI) 193.01, is one of the few such planets discovered to date, and the first example of an ultrahot Neptune. The planet's bulk density indicates that it has a substantial atmosphere, so to investigate its atmospheric composition and shed further light on its origin, we obtained Spitzer InfraRed Array Camera secondary eclipse observations of LTT 9779b at 3.6 and 4.5 \u03bcm. We combined the Spitzer observations with a measurement of the secondary eclipse in the TESS bandpass. The resulting secondary eclipse spectrum strongly prefers a model that includes CO absorption over a blackbody spectrum, incidentally making LTT 9779b the first TESS exoplanet (and the first ultrahot Neptune) with evidence of a spectral feature in its atmosphere. We did not find evidence of a thermal inversion, at odds with expectations based on the atmospheres of similarly irradiated hot Jupiters. We also report a nominal dayside brightness temperature of 2305 \u00b1 141 K (based on the 3.6 \u03bcm secondary eclipse measurement), and we constrained the planet's orbital eccentricity to e < 0.01 at the 99.7% confidence level. Together with our analysis of LTT 9779b's thermal phase curves reported in a companion paper, our results set the stage for similar investigations of a larger sample of exoplanets discovered in the hot-Neptune desert, investigations that are key to uncovering the origin of this population.", "doi": "10.3847/2041-8213/abbc70", "issn": "2041-8213", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2020-11-01", "series_number": "1", "volume": "903", "issue": "1", "pages": "Art. No. L6" }, { "id": "authors:qyh3v-rrw04", "collection": "authors", "collection_id": "qyh3v-rrw04", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200210-135516832", "type": "article", "title": "The Spitzer Space Telescope [interview with Michael Werner]", "author": [ { "family_name": "Woods", "given_name": "Paul", "clpid": "Woods-P-M" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" } ], "abstract": "Michael Werner, project scientist of the Spitzer Space Telescope and emeritus chief scientist for astronomy and physics at the Jet Propulsion Laboratory, discusses the legacy of one of NASA's Great Observatories.", "doi": "10.1038/s41550-020-1013-7", "issn": "2397-3366", "publisher": "Nature Publishing Group", "publication": "Nature Astronomy", "publication_date": "2020-04", "series_number": "4", "volume": "4", "issue": "4", "pages": "306-311" }, { "id": "authors:cqzn5-cf828", "collection": "authors", "collection_id": "cqzn5-cf828", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191120-101536409", "type": "article", "title": "K2-19b and c are in a 3:2 Commensurability but out of Resonance: A Challenge to Planet Assembly by Convergent Migration", "author": [ { "family_name": "Petigura", "given_name": "Erik A.", "orcid": "0000-0003-0967-2893", "clpid": "Petigura-E-A" }, { "family_name": "Livingston", "given_name": "John", "orcid": "0000-0002-4881-3620", "clpid": "Livingston-J-H" }, { "family_name": "Batygin", "given_name": "Konstantin", "orcid": "0000-0002-7094-7908", "clpid": "Batygin-K" }, { "family_name": "Mills", "given_name": "Sean M.", "orcid": "0000-0002-4535-6241", "clpid": "Mills-S-M" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "Isaacson", "given_name": "Howard", "orcid": "0000-0002-0531-1073", "clpid": "Isaacson-H-T" }, { "family_name": "Fulton", "given_name": "Benjamin J.", "orcid": "0000-0003-3504-5316", "clpid": "Fulton-B-J" }, { "family_name": "Howard", "given_name": "Andrew W.", "orcid": "0000-0001-8638-0320", "clpid": "Howard-A-W" }, { "family_name": "Weiss", "given_name": "Lauren M.", "orcid": "0000-0002-3725-3058", "clpid": "Weiss-L-M" }, { "family_name": "Espinoza", "given_name": "N\u00e9stor", "orcid": "0000-0001-9513-1449", "clpid": "Espinoza-N" }, { "family_name": "Jontof-Hutter", "given_name": "Daniel", "orcid": "0000-0002-6227-7510", "clpid": "Jontof-Hutter-D" }, { "family_name": "Shporer", "given_name": "Avi", "orcid": "0000-0002-1836-3120", "clpid": "Shporer-A" }, { "family_name": "Bayliss", "given_name": "Daniel", "orcid": "0000-0001-6023-1335", "clpid": "Bayliss-D" }, { "family_name": "Barros", "given_name": "S. C. C.", "orcid": "0000-0003-2434-3625", "clpid": "Barros-S-C-C" } ], "abstract": "K2-19b and c were among the first planets discovered by NASA's K2 mission and together stand in stark contrast with the physical and orbital properties of the solar system planets. The planets are between the size of Uranus and Saturn at 7.0 \u00b1 0.2 R\u2295 and 4.1 \u00b1 0.2 R\u2295, respectively, and reside a mere 0.1% outside the nominal 3:2 mean-motion resonance. They represent a different outcome of the planet formation process than the solar system, as well as the vast majority of known exoplanets. We measured the physical and orbital properties of these planets using photometry from K2, Spitzer, and ground-based telescopes, along with radial velocities from Keck/HIRES. Through a joint photodynamical model, we found that the planets have moderate eccentricities of e \u2248 0.20 and well-aligned apsides \u0394\u03d6 \u2248 0\u00b0. The planets occupy a strictly nonresonant configuration: the resonant angles circulate rather than librate. This defies the predictions of standard formation pathways that invoke convergent or divergent migration, both of which predict \u0394 \u2248 180\u00b0 and eccentricities of a few percent or less. We measured masses of M_(p,b) = 32.4 \u00b1 1.7 M\u2295 and M_(p,c) = 10.8 \u00b1 0.6 M\u2295. Our measurements, with 5% fractional uncertainties, are among the most precise of any sub-Jovian exoplanet. Mass and size reflect a planet's core/envelope structure. Despite having a relatively massive core of M_(core) \u2248 15 M\u2295, K2-19b is envelope-rich, with an envelope mass fraction of roughly 50%. This planet poses a challenge to standard models of core-nucleated accretion, which predict that cores \u227310 M\u2295 will quickly accrete gas and trigger runaway accretion when the envelope mass exceeds that of the core.", "doi": "10.3847/1538-3881/ab5220", "issn": "1538-3881", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2020-01", "series_number": "1", "volume": "159", "issue": "1", "pages": "Art. No. 2" }, { "id": "authors:1sp3t-1m936", "collection": "authors", "collection_id": "1sp3t-1m936", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190124-122613632", "type": "article", "title": "Revisiting the HIP 41378 system with K2 and Spitzer", "author": [ { "family_name": "Berardo", "given_name": "David", "clpid": "Berardo-D" }, { "family_name": "Crossfield", "given_name": "Ian J. M.", "orcid": "0000-0002-1835-1891", "clpid": "Crossfield-I-J-M" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "Petigura", "given_name": "Erik", "orcid": "0000-0003-0967-2893", "clpid": "Petigura-E-A" }, { "family_name": "Christiansen", "given_name": "Jessie", "orcid": "0000-0002-8035-4778", "clpid": "Christiansen-J-L" }, { "family_name": "Ciardi", "given_name": "David R.", "orcid": "0000-0002-5741-3047", "clpid": "Ciardi-D-R" }, { "family_name": "Dressing", "given_name": "Courtney", "orcid": "0000-0001-8189-0233", "clpid": "Dressing-C-D" }, { "family_name": "Fulton", "given_name": "Benjamin J.", "orcid": "0000-0003-3504-5316", "clpid": "Fulton-B-J" }, { "family_name": "Gorjian", "given_name": "Varoujan", "clpid": "Gorjian-V" }, { "family_name": "Greene", "given_name": "Thomas P.", "orcid": "0000-0002-8963-8056", "clpid": "Greene-T-P" }, { "family_name": "Hardegree-Ullman", "given_name": "Kevin", "orcid": "0000-0003-3702-0382", "clpid": "Hardegree-Ullman-K-K" }, { "family_name": "Kane", "given_name": "Stephen R.", "orcid": "0000-0002-7084-0529", "clpid": "Kane-S-R" }, { "family_name": "Livingston", "given_name": "John", "orcid": "0000-0002-4881-3620", "clpid": "Livingston-J-H" }, { "family_name": "Morales", "given_name": "Farisa", "orcid": "0000-0001-9414-3851", "clpid": "Morales-F-Y" }, { "family_name": "Schlieder", "given_name": "Joshua E.", "orcid": "0000-0001-5347-7062", "clpid": "Schlieder-J-E" } ], "abstract": "We present new observations of the multiplanet system HIP 41378, a bright star (V = 8.9, K_s = 7.7) with five known transiting planets. Previous K2 observations showed multiple transits of two Neptune-sized bodies and single transits of three larger planets (R_P = 0.33R_J , 0.47R_J , 0.88R_J ). K2recently observed the system again in Campaign 18 (C18). We observe one new transit each of two of the larger planets d/f, giving maximal orbital periods of 1114/1084 days, as well as integer divisions of these values down to a lower limit of about 50 days. We use all available photometry to determine the eccentricity distributions of HIP 41378 d & f, finding that periods \u227e300 days require non-zero eccentricity. We check for overlapping orbits of planets d and f to constrain their mutual periods, finding that short periods (P < 300 days) for planet f are disfavored. We also observe transits of planets b and c with Spitzer/Infrared Array Camera (IRAC), which we combine with the K2observations to search for transit timing variations (TTVs). We find a linear ephemeris for planet b, but see a significant TTV signal for planet c. The ability to recover the two smaller planets with Spitzer shows that this fascinating system will continue to be detectable with Spitzer, CHEOPS, TESS, and other observatories, allowing us to precisely determine the periods of d and f, characterize the TTVs of planet c, recover the transits of planet e, and further enhance our view of this remarkable dynamical laboratory.", "doi": "10.3847/1538-3881/ab100c", "issn": "1538-3881", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2019-05", "series_number": "5", "volume": "157", "issue": "5", "pages": "Art. No. 185" }, { "id": "authors:vrmtd-wb068", "collection": "authors", "collection_id": "vrmtd-wb068", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190124-122559376", "type": "article", "title": "Spitzer transit follow-up of planet candidates from the K2 mission", "author": [ { "family_name": "Livingston", "given_name": "John H.", "orcid": "0000-0002-4881-3620", "clpid": "Livingston-J-H" }, { "family_name": "Crossfield", "given_name": "Ian J. M.", "orcid": "0000-0002-1835-1891", "clpid": "Crossfield-I-J-M" }, { "family_name": "Werner", "given_name": "Michael W.", "clpid": "Werner-M-W" }, { "family_name": "Gorjian", "given_name": "Varoujan", "clpid": "Gorjian-V" }, { "family_name": "Petigura", "given_name": "Erik A.", "orcid": "0000-0003-0967-2893", "clpid": "Petigura-E-A" }, { "family_name": "Ciardi", "given_name": "David R.", "orcid": "0000-0002-5741-3047", "clpid": "Ciardi-D-R" }, { "family_name": "Dressing", "given_name": "Courtney D.", "orcid": "0000-0001-8189-0233", "clpid": "Dressing-C-D" }, { "family_name": "Fulton", "given_name": "Benjamin J.", "orcid": "0000-0003-3504-5316", "clpid": "Fulton-B-J" }, { "family_name": "Hirano", "given_name": "Teruyuki", "orcid": "0000-0003-3618-7535", "clpid": "Hirano-Teruyuki" }, { "family_name": "Schlieder", "given_name": "Joshua E.", "orcid": "0000-0001-5347-7062", "clpid": "Schlieder-J-E" }, { "family_name": "Sinukoff", "given_name": "Evan", "orcid": "0000-0002-5658-0601", "clpid": "Sinukoff-E" }, { "family_name": "Kosiarek", "given_name": "Molly", "orcid": "0000-0002-6115-4359", "clpid": "Kosiarek-M-R" }, { "family_name": "Akeson", "given_name": "Rachel", "orcid": "0000-0001-9674-1564", "clpid": "Akeson-R-L" }, { "family_name": "Beichman", "given_name": "Charles A.", "orcid": "0000-0002-5627-5471", "clpid": "Beichman-C-A" }, { "family_name": "Benneke", "given_name": "Bj\u00f6rn", "orcid": "0000-0001-5578-1498", "clpid": "Benneke-B" }, { "family_name": "Christiansen", "given_name": "Jessie L.", "orcid": "0000-0002-8035-4778", "clpid": "Christiansen-J-L" }, { "family_name": "Hansen", "given_name": "Bradley M. S.", "orcid": "0000-0001-7840-3502", "clpid": "Hansen-B-M-S" }, { "family_name": "Howard", "given_name": "Andrew W.", "orcid": "0000-0001-8638-0320", "clpid": "Howard-A-W" }, { "family_name": "Isaacson", "given_name": "Howard", "orcid": "0000-0002-0531-1073", "clpid": "Isaacson-H-T" }, { "family_name": "Knutson", "given_name": "Heather A.", "orcid": "0000-0002-5375-4725", "clpid": "Knutson-H-A" }, { "family_name": "Krick", "given_name": "Jessica", "clpid": "Krick-J-E" }, { "family_name": "Martinez", "given_name": "Arturo O.", "orcid": "0000-0002-3311-4085", "clpid": "Martinez-A-O" }, { "family_name": "Sato", "given_name": "Bun'ei", "clpid": "Sato-Bun'ei" }, { "family_name": "Tamura", "given_name": "Motohide", "orcid": "0000-0002-6510-0681", "clpid": "Tamura-Motohide" } ], "abstract": "We present precision 4.5 \u00b5m Spitzer transit photometry of eight planet candidates discovered by the K2 mission: K2-52 b, K2-53 b, EPIC 205084841.01, K2-289 b, K2-174 b, K2-87 b, K2-90 b, and K2-124 b. The sample includes four sub-Neptunes and two sub-Saturns, with radii between 2.6 and 18 R\u2295 and equilibrium temperatures between 440 and 2000 K. In this paper we identify several targets of potential interest for future characterization studies, demonstrate the utility of transit follow-up observations for planet validation and ephemeris refinement, and present new imaging and spectroscopy data. Our simultaneous analysis of the K2 and Spitzer light curves yields improved estimates of the planet radii and multiwavelength information that helps validate their planetary nature, including the previously unvalidated candidate EPIC 205686202.01 (K2-289 b). Our Spitzerobservations yield an order-of-magnitude increase in ephemeris precision, thus paving the way for efficient future study of these interesting systems by reducing the typical transit timing uncertainty in mid-2021 from several hours to a dozen or so minutes. K2-53 b, K2-289 b, K2-174 b, K2-87 b, and K2-90 b are promising radial velocity (RV) targets given the performance of spectrographs available today or in development, and the M3V star K2-124 hosts a temperate sub-Neptune that is potentially a good target for both RV and atmospheric characterization studies.", "doi": "10.3847/1538-3881/aaff69", "issn": "1538-3881", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2019-03", "series_number": "3", "volume": "157", "issue": "3", "pages": "Art. No. 102" }, { "id": "authors:7z9yv-wrk65", "collection": "authors", "collection_id": "7z9yv-wrk65", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181115-105031850", "type": "article", "title": "Spitzer Observations of Interstellar Object 1I/'Oumuamua", "author": [ { "family_name": "Trilling", "given_name": "David E.", "orcid": "0000-0003-4580-3790", "clpid": "Trilling-D-E" }, { "family_name": "Mommert", "given_name": "Michael", "orcid": "0000-0002-8132-778X", "clpid": "Mommert-M" }, { "family_name": "Hora", "given_name": "Joseph L.", "orcid": "0000-0002-5599-4650", "clpid": "Hora-J-L" }, { "family_name": "Farnocchia", "given_name": "Davide", "orcid": "0000-0003-0774-884X", "clpid": "Farnocchia-D" }, { "family_name": "Chodas", "given_name": "Paul", "clpid": "Chodas-P" }, { "family_name": "Giorgini", "given_name": "Jon", "clpid": "Giorgini-J-D" }, { "family_name": "Smith", "given_name": "Howard A.", "clpid": "Smith-H-A" }, { "family_name": "Carey", "given_name": "Sean", "orcid": "0000-0002-0221-6871", "clpid": "Carey-S-J" }, { "family_name": "Lisse", "given_name": "Carey M.", "orcid": "0000-0002-9548-1526", "clpid": "Lisse-C-M" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "McNeill", "given_name": "Andrew", "clpid": "McNeill-A" }, { "family_name": "Chesley", "given_name": "Steven R.", "orcid": "0000-0003-3240-6497", "clpid": "Chesley-S-R" }, { "family_name": "Emery", "given_name": "Joshua P.", "clpid": "Emery-J-P" }, { "family_name": "Fazio", "given_name": "Giovanni", "orcid": "0000-0002-0670-0708", "clpid": "Fazio-G-G" }, { "family_name": "Fernandez", "given_name": "Yanga R.", "orcid": "0000-0003-1156-9721", "clpid": "Fern\u00e1ndez-Y-R" }, { "family_name": "Harris", "given_name": "Alan", "orcid": "0000-0001-7431-2013", "clpid": "Harris-A-W" }, { "family_name": "Marengo", "given_name": "Massimo", "orcid": "0000-0001-9910-9230", "clpid": "Marengo-M" }, { "family_name": "Mueller", "given_name": "Michael", "clpid": "Mueller-M-E" }, { "family_name": "Roegge", "given_name": "Alissa", "clpid": "Roegge-A" }, { "family_name": "Smith", "given_name": "Nathan", "clpid": "Smith-N" }, { "family_name": "Weaver", "given_name": "H. A.", "orcid": "0000-0003-0951-7762", "clpid": "Weaver-H-A" }, { "family_name": "Meech", "given_name": "Karen", "orcid": "0000-0002-2058-5670", "clpid": "Meech-K-J" }, { "family_name": "Micheli", "given_name": "Marco", "orcid": "0000-0001-7895-8209", "clpid": "Micheli-M" } ], "abstract": "1I/'Oumuamua is the first confirmed interstellar body in our solar system. Here we report on observations of 'Oumuamua made with the Spitzer Space Telescope on 2017 November 21\u201322 (UT). We integrated for 30.2 hr at 4.5 \u03bcm (IRAC channel 2). We did not detect the object and place an upper limit on the flux of 0.3 \u03bcJy (3\u03c3). This implies an effective spherical diameter less than [98, 140, 440] m and albedo greater than [0.2, 0.1, 0.01] under the assumption of low, middle, or high thermal beaming parameter \u03b7, respectively. With an aspect ratio for 'Oumuamua of 6:1, these results correspond to dimensions of [240:40, 341:57, 1080:180] m, respectively. We place upper limits on the amount of dust, CO, and CO2 coming from this object that are lower than previous results; we are unable to constrain the production of other gas species. Both our size and outgassing limits are important because 'Oumuamua's trajectory shows non-gravitational accelerations that are sensitive to size and mass and presumably caused by gas emission. We suggest that 'Oumuamua may have experienced low-level post-perihelion volatile emission that produced a fresh, bright, icy mantle. This model is consistent with the expected \u03b7 value and implied high-albedo value for this solution, but, given our strict limits on CO and CO_2, requires another gas species\u2014probably H_2O\u2014to explain the observed non-gravitational acceleration. Our results extend the mystery of 'Oumuamua's origin and evolution.", "doi": "10.3847/1538-3881/aae88f", "issn": "1538-3881", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2018-12", "series_number": "6", "volume": "156", "issue": "6", "pages": "Art. No. 261" }, { "id": "authors:9w7gb-pas65", "collection": "authors", "collection_id": "9w7gb-pas65", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180928-100943536", "type": "article", "title": "Astrophysics with New Horizons: Making the Most of a Generational Opportunity", "author": [ { "family_name": "Zemcov", "given_name": "Michael", "orcid": "0000-0001-8253-1451", "clpid": "Zemcov-M" }, { "family_name": "Arcavi", "given_name": "Iair", "orcid": "0000-0001-7090-4898", "clpid": "Arcavi-I" }, { "family_name": "Arendt", "given_name": "Richard", "orcid": "0000-0001-8403-8548", "clpid": "Arendt-R-G" }, { "family_name": "Bachelet", "given_name": "Etienne", "orcid": "0000-0002-6578-5078", "clpid": "Bachelet-E" }, { "family_name": "Chary", "given_name": "Ranga Ram", "orcid": "0000-0001-7583-0621", "clpid": "Chary-R-R" }, { "family_name": "Cooray", "given_name": "Asantha", "orcid": "0000-0002-3892-0190", "clpid": "Cooray-A" }, { "family_name": "Dragomir", "given_name": "Diana", "orcid": "0000-0003-2313-467X", "clpid": "Dragomir-D" }, { "family_name": "Henry", "given_name": "Richard Conn", "clpid": "Henry-R-C" }, { "family_name": "Lisse", "given_name": "Carey", "orcid": "0000-0002-9548-1526", "clpid": "Lisse-C-M" }, { "family_name": "Matsuura", "given_name": "Shuji", "orcid": "0000-0002-5698-9634", "clpid": "Matsuura-Shuji" }, { "family_name": "Murthy", "given_name": "Jayant", "clpid": "Murthy-J" }, { "family_name": "Nguyen", "given_name": "Chi", "clpid": "Nguyen-Chi-H" }, { "family_name": "Poppe", "given_name": "Andrew R.", "clpid": "Poppe-A-R" }, { "family_name": "Street", "given_name": "Rachel", "orcid": "0000-0001-6279-0552", "clpid": "Street-R-A" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" } ], "abstract": "The outer solar system provides a unique, quiet vantage point from which to observe the universe around us, where measurements could enable several niche astrophysical science cases that are too difficult to perform near Earth. NASA's New Horizons mission comprises an instrument package that provides imaging capability from ultraviolet (UV) to near-infrared (near-IR) wavelengths with moderate spectral resolution located beyond the orbit of Pluto. A carefully designed survey with New Horizons can optimize the use of expendable propellant and the limited data telemetry bandwidth to allow several measurements, including a detailed understanding of the cosmic extragalactic background light; studies of the local and extragalactic UV background; measurements of the properties of dust and ice in the outer solar system; confirmation and characterization of transiting exoplanets; determinations of the mass of dark objects using gravitational microlensing; and rapid follow-up of transient events. New Horizons is currently in an extended mission designed to focused on Kuiper Belt science that will conclude in 2021. The astrophysics community has a unique, generational opportunity to use this mission for astronomical observation at heliocentric distances beyond 50 au in the next decade. In this paper, we discuss the potential science cases for such an extended mission, and provide an initial assessment of the most important operational requirements and observation strategies it would require. We conclude that New Horizons is capable of transformative science, and that it would make a valuable and unique asset for astrophysical science that is unlikely to be replicated in the near future.", "doi": "10.1088/1538-3873/aadb77", "issn": "0004-6280", "publisher": "Astronomical Society of the Pacific", "publication": "Publications of the Astronomical Society of the Pacific", "publication_date": "2018-11", "series_number": "993", "volume": "130", "issue": "993", "pages": "Art. No. 115001" }, { "id": "authors:e8tr3-wwq24", "collection": "authors", "collection_id": "e8tr3-wwq24", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180809-101844353", "type": "article", "title": "Dynamics and Formation of the Near-resonant K2-24 System: Insights from Transit-timing Variations and Radial Velocities", "author": [ { "family_name": "Petigura", "given_name": "Erik A.", "orcid": "0000-0003-0967-2893", "clpid": "Petigura-E-A" }, { "family_name": "Benneke", "given_name": "Bj\u00f6rn", "orcid": "0000-0001-5578-1498", "clpid": "Benneke-B" }, { "family_name": "Batygin", "given_name": "Konstantin", "orcid": "0000-0002-7094-7908", "clpid": "Batygin-K" }, { "family_name": "Fulton", "given_name": "Benjamin J.", "orcid": "0000-0003-3504-5316", "clpid": "Fulton-B-J" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "Krick", "given_name": "Jessica E.", "clpid": "Krick-J-E" }, { "family_name": "Gorjian", "given_name": "Varoujan", "clpid": "Gorjian-V" }, { "family_name": "Sinukoff", "given_name": "Evan", "orcid": "0000-0002-5658-0601", "clpid": "Sinukoff-E" }, { "family_name": "Deck", "given_name": "Katherine M.", "clpid": "Deck-K-M" }, { "family_name": "Mills", "given_name": "Sean M.", "orcid": "0000-0002-4535-6241", "clpid": "Mills-S-M" }, { "family_name": "Deming", "given_name": "Drake", "orcid": "0000-0001-5727-4094", "clpid": "Deming-D" } ], "abstract": "While planets between the size of Uranus and Saturn are absent within the solar system, the star K2-24 hosts two such planets, K2-24b and c, with radii equal to 5.4 R\u2295 and 7.5 R\u2295, respectively. The two planets have orbital periods of 20.9 days and 42.4 days, residing only 1% outside the nominal 2:1 mean-motion resonance. In this work, we present results from a coordinated observing campaign to measure planet masses and eccentricities that combines radial velocity measurements from Keck/HIRES and transit-timing measurements from K2 and Spitzer. K2-24b and c have low, but nonzero, eccentricities of e_1 ~ e_2 ~ 0.08. The low observed eccentricities provide clues to the formation and dynamical evolution of K2-24b and K2-24c, suggesting that they could be the result of stochastic gravitational interactions with a turbulent protoplanetary disk, among other mechanisms. K2-24b and c are 19.0^(+2.2)_(-2.1) M\u2295 and 15.4^(+1.9)_(-1.8) M\u2295, respectively; K2-24c is 20% less massive than K2-24b, despite being 40% larger. Their large sizes and low masses imply large envelope fractions, which we estimate at 26^(+3)_(-3)% and 52^(+5)_(-3)%. In particular, K2-24c's large envelope presents an intriguing challenge to the standard model of core-nucleated accretion that predicts the onset of runaway accretion when \u222b_(env) \u2248 50%.", "doi": "10.3847/1538-3881/aaceac", "issn": "1538-3881", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2018-09", "series_number": "3", "volume": "156", "issue": "3", "pages": "Art. No. 89" }, { "id": "authors:pxxjt-80627", "collection": "authors", "collection_id": "pxxjt-80627", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180809-100535642", "type": "article", "title": "Characterizing K2 Candidate Planetary Systems Orbiting Low-mass Stars. III. A High Mass and Low Envelope Fraction for the Warm Neptune K2-55b", "author": [ { "family_name": "Dressing", "given_name": "Courtney D.", "orcid": "0000-0001-8189-0233", "clpid": "Dressing-C-D" }, { "family_name": "Sinukoff", "given_name": "Evan", "orcid": "0000-0002-5658-0601", "clpid": "Sinukoff-E" }, { "family_name": "Fulton", "given_name": "Benjamin J.", "orcid": "0000-0003-3504-5316", "clpid": "Fulton-B-J" }, { "family_name": "Lopez", "given_name": "Eric D.", "clpid": "Lopez-E-D" }, { "family_name": "Beichman", "given_name": "Charles A.", "orcid": "0000-0002-5627-5471", "clpid": "Beichman-C-A" }, { "family_name": "Howard", "given_name": "Andrew W.", "orcid": "0000-0001-8638-0320", "clpid": "Howard-A-W" }, { "family_name": "Knutson", "given_name": "Heather A.", "orcid": "0000-0002-5375-4725", "clpid": "Knutson-H-A" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "Benneke", "given_name": "Bj\u00f6rn", "orcid": "0000-0001-5578-1498", "clpid": "Benneke-B" }, { "family_name": "Crossfield", "given_name": "Ian J. M.", "orcid": "0000-0002-1835-1891", "clpid": "Crossfield-I-J-M" }, { "family_name": "Isaacson", "given_name": "Howard", "orcid": "0000-0002-0531-1073", "clpid": "Isaacson-H-T" }, { "family_name": "Krick", "given_name": "Jessica", "clpid": "Krick-J-E" }, { "family_name": "Gorjian", "given_name": "Varoujan", "clpid": "Gorjian-V" }, { "family_name": "Livingston", "given_name": "John", "orcid": "0000-0002-4881-3620", "clpid": "Livingston-J-H" }, { "family_name": "Petigura", "given_name": "Erik A.", "orcid": "0000-0003-0967-2893", "clpid": "Petigura-E-A" }, { "family_name": "Schlieder", "given_name": "Joshua E.", "orcid": "0000-0001-5347-7062", "clpid": "Schlieder-J-E" }, { "family_name": "Akeson", "given_name": "Rachel L.", "orcid": "0000-0001-9674-1564", "clpid": "Akeson-R-L" }, { "family_name": "Batygin", "given_name": "Konstantin", "orcid": "0000-0002-7094-7908", "clpid": "Batygin-K" }, { "family_name": "Christiansen", "given_name": "Jessie L.", "orcid": "0000-0002-8035-4778", "clpid": "Christiansen-J-L" }, { "family_name": "Ciardi", "given_name": "David R.", "orcid": "0000-0002-5741-3047", "clpid": "Ciardi-D-R" }, { "family_name": "Crepp", "given_name": "Justin R.", "orcid": "0000-0003-0800-0593", "clpid": "Crepp-J-R" }, { "family_name": "Gonzales", "given_name": "Erica J.", "clpid": "Gonzales-E-J" }, { "family_name": "Hardegree-Ullman", "given_name": "Kevin K.", "orcid": "0000-0003-3702-0382", "clpid": "Hardegree-Ullman-K-K" }, { "family_name": "Hirsch", "given_name": "Lea A.", "orcid": "0000-0001-8058-7443", "clpid": "Hirsch-L-A" }, { "family_name": "Kosiarek", "given_name": "Molly", "orcid": "0000-0002-6115-4359", "clpid": "Kosiarek-M-R" }, { "family_name": "Weiss", "given_name": "Lauren M.", "orcid": "0000-0002-3725-3058", "clpid": "Weiss-L-M" } ], "abstract": "K2-55b is a Neptune-sized planet orbiting a K7 dwarf with a radius of , a mass of 0.688 \u00b1 0.069 M\u2299, and an effective temperature of 4300^(+107)_(-100) K. Having characterized the host star using near-infrared spectra obtained at IRTF/SpeX, we observed a transit of K2-55b with Spitzer/Infrared Array Camera (IRAC) and confirmed the accuracy of the original K2 ephemeris for future follow-up transit observations. Performing a joint fit to the Spitzer/IRAC and K2 photometry, we found a planet radius of 4.41^(+0.32)_(-0.28) R\u2295, an orbital period of 2.84927265^(+6.87 x 10^(-6))_(-6.42 x 10^(-6)) days, and an equilibrium temperature of roughly 900 K. We then measured the planet mass by acquiring 12 radial velocity (RV) measurements of the system using the High Resolution Echelle Spectrometer on the 10 m Keck I Telescope. Our RV data set precisely constrains the mass of K2-55b to 43.13^(+5.98)_(-5.80) M\u2295, indicating that K2-55b has a bulk density of 2.8^(+0.8)_(-0.6) g cm^(\u22123) and can be modeled as a rocky planet capped by a modest H/He envelope (M_(envelope) = 12 \u00b1 3% M_p ). K2-55b is denser than most similarly sized planets, raising the question of whether the high planetary bulk density of K2-55b could be attributed to the high metallicity of K2-55. The absence of a substantial volatile envelope despite the high mass of K2-55b poses a challenge to current theories of gas giant formation. We posit that K2-55b may have escaped runaway accretion by migration, late formation, or inefficient core accretion, or that K2-55b was stripped of its envelope by a late giant impact.", "doi": "10.3847/1538-3881/aacf99", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2018-08", "series_number": "2", "volume": "156", "issue": "2", "pages": "Art. No. 70" }, { "id": "authors:gyxcc-3r516", "collection": "authors", "collection_id": "gyxcc-3r516", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180503-134842697", "type": "article", "title": "An Improved Transit Measurement for a 2.4 R\u2295 Planet Orbiting A Bright Mid-M Dwarf K2\u201328", "author": [ { "family_name": "Chen", "given_name": "Ge", "orcid": "0000-0003-2867-4544", "clpid": "Chen-Ge" }, { "family_name": "Knutson", "given_name": "Heather A.", "orcid": "0000-0002-5375-4725", "clpid": "Knutson-H-A" }, { "family_name": "Dressing", "given_name": "Courtney D.", "orcid": "0000-0001-8189-0233", "clpid": "Dressing-C-D" }, { "family_name": "Morley", "given_name": "Caroline V.", "orcid": "0000-0002-4404-0456", "clpid": "Morley-C-V" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "Gorjian", "given_name": "Varoujan", "clpid": "Gorjian-V" }, { "family_name": "Beichman", "given_name": "Charles", "orcid": "0000-0002-5627-5471", "clpid": "Beichman-C-A" }, { "family_name": "Benneke", "given_name": "Bj\u00f6rn", "orcid": "0000-0001-5578-1498", "clpid": "Benneke-B" }, { "family_name": "Christiansen", "given_name": "Jessie L.", "orcid": "0000-0002-8035-4778", "clpid": "Christiansen-J-L" }, { "family_name": "Ciardi", "given_name": "David", "orcid": "0000-0002-5741-3047", "clpid": "Ciardi-D-R" }, { "family_name": "Crossfield", "given_name": "Ian", "orcid": "0000-0002-1835-1891", "clpid": "Crossfield-I-J-M" }, { "family_name": "Howell", "given_name": "Steve B.", "orcid": "0000-0002-2532-2853", "clpid": "Howell-S-B" }, { "family_name": "Krick", "given_name": "Jessica E.", "clpid": "Krick-J-E" }, { "family_name": "Livingston", "given_name": "John", "orcid": "0000-0002-4881-3620", "clpid": "Livingston-J-H" }, { "family_name": "Morales", "given_name": "Farisa Y.", "orcid": "0000-0001-9414-3851", "clpid": "Morales-F-Y" }, { "family_name": "Schlieder", "given_name": "Joshua E.", "orcid": "0000-0001-5347-7062", "clpid": "Schlieder-J-E" } ], "abstract": "We present a new Spitzer transit observation of K2\u201328b, a sub-Neptune (Rp = 2.45 \u00b1 0.28 R\u2295) orbiting a relatively bright (V_(mag) = 16.06, K_(mag) = 10.75) metal-rich M4 dwarf (EPIC 206318379). This star is one of only seven with masses less than 0.2 M\u2299 known to host transiting planets, and the planet appears to be a slightly smaller analogue of GJ 1214b (2.85 \u00b1 0.20 R\u2295). Our new Spitzerobservations were taken two years after the original K2 discovery data and have a significantly higher cadence, allowing us to derive improved estimates for this planet's radius, semimajor axis, and orbital period, which greatly reduce the uncertainty in the prediction of near future transit times for the James Webb Space Telescope (JWST) observations. We also evaluate the system's suitability for atmospheric characterization with JWST and find that it is currently the only small (<3 R\u2295) and cool (<600 K) planet aside from GJ 1214b with a potentially detectable secondary eclipse. We also note that this system is a favorable target for near-infrared radial velocity instruments on larger telescopes (e.g., the Habitable Planet Finder on the Hobby\u2013Eberly Telescope), making it one of only a handful of small, cool planets accessible with this technique. Finally, we compare our results with the simulated catalog of the Transiting Exoplanet Survey Satellite (TESS) and find K2\u201328b to be representative of the kind of mid-M systems that should be detectable in the TESS sample.", "doi": "10.3847/1538-3881/aabd75", "issn": "1538-3881", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2018-05", "series_number": "5", "volume": "155", "issue": "5", "pages": "Art. No. 223" }, { "id": "authors:bc950-pky64", "collection": "authors", "collection_id": "bc950-pky64", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170306-133641378", "type": "article", "title": "Stellar and Planetary Parameters for K2's Late-type Dwarf Systems from C1 to C5", "author": [ { "family_name": "Martinez", "given_name": "Arturo O.", "orcid": "0000-0002-3311-4085", "clpid": "Martinez-A-O" }, { "family_name": "Crossfield", "given_name": "Ian J. M.", "orcid": "0000-0002-1835-1891", "clpid": "Crossfield-I-J-M" }, { "family_name": "Schlieder", "given_name": "Joshua E.", "orcid": "0000-0001-5347-7062", "clpid": "Schlieder-J-E" }, { "family_name": "Dressing", "given_name": "Courtney D.", "orcid": "0000-0001-8189-0233", "clpid": "Dressing-C-D" }, { "family_name": "Obermeier", "given_name": "Christian", "clpid": "Obermeier-C" }, { "family_name": "Livingston", "given_name": "John", "orcid": "0000-0002-4881-3620", "clpid": "Livingston-J-H" }, { "family_name": "Ciceri", "given_name": "Simona", "clpid": "Ciceri-S" }, { "family_name": "Peacock", "given_name": "Sarah", "orcid": "0000-0002-1046-025X", "clpid": "Peacock-S" }, { "family_name": "Beichman", "given_name": "Charles A.", "orcid": "0000-0002-5627-5471", "clpid": "Beichman-C-A" }, { "family_name": "L\u00e9pine", "given_name": "S\u00e9bastien", "orcid": "0000-0002-2437-2947", "clpid": "L\u00e9pine-S" }, { "family_name": "Aller", "given_name": "Kimberly M.", "orcid": "0000-0003-0208-6146", "clpid": "Aller-K-M" }, { "family_name": "Chance", "given_name": "Quadry A.", "clpid": "Chance-Q-A" }, { "family_name": "Petigura", "given_name": "Erik A.", "orcid": "0000-0003-0967-2893", "clpid": "Petigura-E-A" }, { "family_name": "Howard", "given_name": "Andrew W.", "orcid": "0000-0001-8638-0320", "clpid": "Howard-A-W" }, { "family_name": "Werner", "given_name": "Michael W.", "clpid": "Werner-M-W" } ], "abstract": "The NASA K2 mission uses photometry to find planets transiting stars of various types. M dwarfs are of high interest since they host more short-period planets than any other type of main-sequence star and transiting planets around M dwarfs have deeper transits compared to other main-sequence stars. In this paper, we present stellar parameters from K and M dwarfs hosting transiting planet candidates discovered by our team. Using the SOFI spectrograph on the European Southern Observatory's New Technology Telescope, we obtained R \u2248 1000 J-, H-, and K-band (0.95\u20132.52 \u03bcm) spectra of 34 late-type K2 planet and candidate planet host systems and 12 bright K4\u2013M5 dwarfs with interferometrically measured radii and effective temperatures. Out of our 34 late-type K2 targets, we identify 27 of these stars as M dwarfs. We measure equivalent widths of spectral features, derive calibration relations using stars with interferometric measurements, and estimate stellar radii, effective temperatures, masses, and luminosities for the K2 planet hosts. Our calibrations provide radii and temperatures with median uncertainties of 0.059 R\u2299 (16.09%) and 160 K (4.33%), respectively. We then reassess the radii and equilibrium temperatures of known and candidate planets based on our spectroscopically derived stellar parameters. Since a planet's radius and equilibrium temperature depend on the parameters of its host star, our study provides more precise planetary parameters for planets and candidates orbiting late-type stars observed with K2. We find a median planet radius and an equilibrium temperature of approximately 3 R\u2295 and 500 K, respectively, with several systems (K2-18b and K2-72e) receiving near-Earth-like levels of incident irradiation.", "doi": "10.3847/1538-4357/aa56c7", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2017-03-01", "series_number": "1", "volume": "837", "issue": "1", "pages": "Art. No. 72" }, { "id": "authors:44pvn-eat24", "collection": "authors", "collection_id": "44pvn-eat24", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170120-091021457", "type": "article", "title": "Spitzer Observations Confirm and Rescue the Habitable-zone Super-Earth K2-18b for Future Characterization", "author": [ { "family_name": "Benneke", "given_name": "Bj\u00f6rn", "orcid": "0000-0001-5578-1498", "clpid": "Benneke-B" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "Petigura", "given_name": "Erik A.", "orcid": "0000-0003-0967-2893", "clpid": "Petigura-E-A" }, { "family_name": "Knutson", "given_name": "Heather", "orcid": "0000-0002-5375-4725", "clpid": "Knutson-H-A" }, { "family_name": "Dressing", "given_name": "Courtney", "orcid": "0000-0001-8189-0233", "clpid": "Dressing-C-D" }, { "family_name": "Crossfield", "given_name": "Ian J. M.", "orcid": "0000-0002-1835-1891", "clpid": "Crossfield-I-J-M" }, { "family_name": "Schlieder", "given_name": "Joshua E.", "orcid": "0000-0001-5347-7062", "clpid": "Schlieder-J-E" }, { "family_name": "Livingston", "given_name": "John", "clpid": "Livingston-J-M" }, { "family_name": "Beichman", "given_name": "Charles", "orcid": "0000-0002-5627-5471", "clpid": "Beichman-C-A" }, { "family_name": "Christiansen", "given_name": "Jessie", "orcid": "0000-0002-8035-4778", "clpid": "Christiansen-J-L" }, { "family_name": "Krick", "given_name": "Jessica", "clpid": "Krick-J-E" }, { "family_name": "Gorjian", "given_name": "Varoujan", "clpid": "Gorjian-V" }, { "family_name": "Howard", "given_name": "Andrew W.", "orcid": "0000-0001-8638-0320", "clpid": "Howard-A-W" }, { "family_name": "Sinukoff", "given_name": "Evan", "orcid": "0000-0002-5658-0601", "clpid": "Sinukoff-E" }, { "family_name": "Ciardi", "given_name": "David R.", "orcid": "0000-0002-5741-3047", "clpid": "Ciardi-D-R" }, { "family_name": "Akeson", "given_name": "Rachel L.", "orcid": "0000-0001-9674-1564", "clpid": "Akeson-R-L" } ], "abstract": "The recent detections of two transit events attributed to the super-Earth candidate K2-18b have provided the unprecedented prospect of spectroscopically studying a habitable-zone planet outside the solar system. Orbiting a nearby M2.5 dwarf and receiving virtually the same stellar insolation as Earth, K2-18b would be a prime candidate for the first detailed atmospheric characterization of a habitable-zone exoplanet using the Hubble Space Telescope (HST)and James Webb Space Telescope (JWST). Here, we report the detection of a third transit of K2-18b near the predicted transit time using the Spitzer Space Telescope. The Spitzer detection demonstrates the periodic nature of the two transit events discovered by K2, confirming that K2-18 is indeed orbited by a super-Earth in a 33 day orbit, ruling out the alternative scenario of two similarly sized, long-period planets transiting only once within the 75 day Kepler Space Telescope (K2) observation. We also find, however, that the transit event detected by Spitzer occurred 1.85 hr ($7\\sigma $) before the predicted transit time. Our joint analysis of the Spitzer and K2 photometry reveals that this early occurrence of the transit is not caused by transit timing variations, but the result of an inaccurate ephemeris due to a previously undetected data anomaly in the K2 photometry. We refit the ephemeris and find that K2-18b would have been lost for future atmospheric characterizations with HST and JWST if we had not secured its ephemeris shortly after the discovery. We caution that immediate follow-up observations as presented here will also be critical for confirming and securing future planets discovered by the Transiting Exoplanet Survey Satellite (TESS), in particular if only two transit events are covered by the relatively short 27-day TESS campaigns.", "doi": "10.3847/1538-4357/834/2/187", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2017-01-10", "series_number": "2", "volume": "834", "issue": "2", "pages": "Art. No. 187" }, { "id": "authors:zbzyf-2yv16", "collection": "authors", "collection_id": "zbzyf-2yv16", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161012-073815704", "type": "article", "title": "Spitzer Observations of Exoplanets Discovered with The Kepler K2 Mission", "author": [ { "family_name": "Beichman", "given_name": "Charles", "orcid": "0000-0002-5627-5471", "clpid": "Beichman-C-A" }, { "family_name": "Livingston", "given_name": "John", "clpid": "Livingston-J-M" }, { "family_name": "Werner", "given_name": "Michael", "clpid": "Werner-M-W" }, { "family_name": "Gorjian", "given_name": "Varoujan", "clpid": "Gorjian-V" }, { "family_name": "Krick", "given_name": "Jessica", "clpid": "Krick-J-E" }, { "family_name": "Deck", "given_name": "Katherine", "clpid": "Deck-K-M" }, { "family_name": "Knutson", "given_name": "Heather", "orcid": "0000-0002-5375-4725", "clpid": "Knutson-H-A" }, { "family_name": "Wong", "given_name": "Ian", "orcid": "0000-0001-9665-8429", "clpid": "Wong-Ian" }, { "family_name": "Petigura", "given_name": "Erik", "orcid": "0000-0003-0967-2893", "clpid": "Petigura-E-A" }, { "family_name": "Christiansen", "given_name": "Jessie", "orcid": "0000-0002-8035-4778", "clpid": "Christiansen-J-L" }, { "family_name": "Ciardi", "given_name": "David", "orcid": "0000-0002-5741-3047", "clpid": "Ciardi-D-R" }, { "family_name": "Greene", "given_name": "Thomas P.", "orcid": "0000-0002-8963-8056", "clpid": "Greene-T-P" }, { "family_name": "Schlieder", "given_name": "Joshua E.", "orcid": "0000-0001-5347-7062", "clpid": "Schlieder-J-E" }, { "family_name": "Line", "given_name": "Mike", "orcid": "0000-0002-2338-476X", "clpid": "Line-M-R" }, { "family_name": "Crossfield", "given_name": "Ian", "orcid": "0000-0002-1835-1891", "clpid": "Crossfield-I-J-M" }, { "family_name": "Howard", "given_name": "Andrew W.", "orcid": "0000-0001-8638-0320", "clpid": "Howard-A-W" }, { "family_name": "Sinukoff", "given_name": "Evan", "orcid": "0000-0002-5658-0601", "clpid": "Sinukoff-E" } ], "abstract": "We have used the Spitzer Space Telescope to observe two transiting planetary systems orbiting low-mass stars discovered in the Kepler K2 mission. The system K2-3 (EPIC 201367065) hosts three planets, while K2-26 (EPIC 202083828) hosts a single planet. Observations of all four objects in these two systems confirm and refine the orbital and physical parameters of the planets. The refined orbital information and more precise planet radii possible with Spitzer will be critical for future observations of these and other K2 targets. For K2-3b we find marginally significant evidence for a transit timing variation between the K2 and Spitzer epochs.", "doi": "10.3847/0004-637X/822/1/39", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2016-05-01", "series_number": "1", "volume": "822", "issue": "1", "pages": "Art. No. 39" }, { "id": "authors:maf2t-e2q55", "collection": "authors", "collection_id": "maf2t-e2q55", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150624-083530992", "type": "article", "title": "Spitzer's stellar work", "author": [ { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Storrie-Lombardi", "given_name": "L.", "orcid": "0000-0002-5987-5210", "clpid": "Storrie-Lombardi-L-J" }, { "family_name": "Helou", "given_name": "G.", "orcid": "0000-0003-3367-3415", "clpid": "Helou-G" } ], "abstract": "In the News Feature \"After Hubble\" (24 April, p. 388), D. Clery inappropriately characterizes the Spitzer Space Telescope as \"now largely blind.\" In fact, Spitzer is alive and well and continuing to make substantial contributions to the advancement of astrophysics and to scientific preparations for the James Webb Space Telescope (JWST). The exhaustion of Spitzer's cryogen in mid-2009 left the observatory with two functioning imaging arrays at wavelengths of 3.6 and 4.5 \u00b5m. The performance of what is now called \"Warm\" Spitzer at these wavelengths matches that achieved during the cryogenic mission. Despite its small size, Spitzer is by far the most sensitive telescope, space or ground, available at these wavelengths. The science community has used Warm Spitzer for important scientific investigations, including studies of exoplanets, the early universe, variable stars to define better the cosmic distance ladder, clusters of galaxies, near-Earth asteroids, and comets. Spitzer remains very much in demand; for the past 2 years, the oversubscription for requested observing time has been the highest of the mission.", "doi": "10.1126/science.348.6241.1326-a", "issn": "0036-8075", "publisher": "American Association for the Advancement of Science", "publication": "Science", "publication_date": "2015-06-19", "series_number": "6241", "volume": "348", "issue": "6241", "pages": "1326" }, { "id": "authors:0wrk7-4v668", "collection": "authors", "collection_id": "0wrk7-4v668", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110506-141702853", "type": "article", "title": "Ices in the Quiescent IC 5146 Dense Cloud", "author": [ { "family_name": "Chiar", "given_name": "J. E.", "clpid": "Chiar-J-E" }, { "family_name": "Pendleton", "given_name": "Y. J.", "clpid": "Pendleton-Y-J" }, { "family_name": "Allamandola", "given_name": "L. J.", "clpid": "Allamandola-L-J" }, { "family_name": "Boogert", "given_name": "A. C. A.", "clpid": "Boogert-A-C-A" }, { "family_name": "Ennico", "given_name": "K.", "orcid": "0000-0002-8847-8492", "clpid": "Ennico-K" }, { "family_name": "Greene", "given_name": "T. P.", "orcid": "0000-0002-8963-8056", "clpid": "Greene-T-P" }, { "family_name": "Geballe", "given_name": "T. R.", "clpid": "Geballe-T-R" }, { "family_name": "Keane", "given_name": "J. V.", "clpid": "Keane-J-V" }, { "family_name": "Lada", "given_name": "C. J.", "clpid": "Lada-C-J" }, { "family_name": "Mason", "given_name": "R. E.", "clpid": "Maso-R-E" }, { "family_name": "Roellig", "given_name": "T. L.", "clpid": "Roellig-T-L" }, { "family_name": "Sandford", "given_name": "S. A.", "clpid": "Sandford-S-A" }, { "family_name": "Tielens", "given_name": "A. G. G. M.", "clpid": "Tielens-A-G-G-M" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Whittet", "given_name": "D. C. B.", "clpid": "Whittet-D-C-B" }, { "family_name": "Decin", "given_name": "L.", "clpid": "Decin-L" }, { "family_name": "Eriksson", "given_name": "K.", "clpid": "Eriksson-K" } ], "abstract": "This paper presents spectra in the 2 to 20 \u03bcm range of quiescent cloud material located in the IC 5146 cloud complex. The spectra were obtained with NASA's Infrared Telescope Facility SpeX instrument and the Spitzer Space Telescope's Infrared Spectrometer. We use these spectra to investigate dust and ice absorption features in pristine regions of the cloud that are unaltered by embedded stars. We find that the H_2O-ice threshold extinction is 4.03 \u00b1 0.05 mag. Once foreground extinction is taken into account, however, the threshold drops to 3.2 mag, equivalent to that found for the Taurus dark cloud, generally assumed to be the touchstone quiescent cloud against which all other dense cloud and embedded young stellar object observations are compared. Substructure in the trough of the silicate band for two sources is attributed to CH_3OH and NH_3 in the ices, present at the ~2% and ~5% levels, respectively, relative to H_2O-ice. The correlation of the silicate feature with the E(J \u2013 K) color excess is found to follow a much shallower slope relative to lines of sight that probe diffuse clouds, supporting the previous results by Chiar et al.", "doi": "10.1088/0004-637X/731/1/9", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2011-04-10", "series_number": "1", "volume": "731", "issue": "1", "pages": "Art. No. 9" }, { "id": "authors:taxfy-vg333", "collection": "authors", "collection_id": "taxfy-vg333", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110808-114801290", "type": "article", "title": "Common Warm Dust Temperatures Around Main-sequence Stars", "author": [ { "family_name": "Morales", "given_name": "Farisa Y.", "orcid": "0000-0001-9414-3851", "clpid": "Morales-F-Y" }, { "family_name": "Rieke", "given_name": "G. H.", "orcid": "0000-0003-2303-6519", "clpid": "Rieke-G-H" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Bryden", "given_name": "G.", "clpid": "Bryden-G" }, { "family_name": "Stapelfeldt", "given_name": "K. R.", "orcid": "0000-0002-2805-7338", "clpid": "Stapelfeldt-K-R" }, { "family_name": "Su", "given_name": "K. Y. L.", "orcid": "0000-0002-3532-5580", "clpid": "Su-Katherine-Y-L" } ], "abstract": "We compare the properties of warm dust emission from a sample of main-sequence A-type stars (B8-A7) to those of dust around solar-type stars (F5-K0) with similar Spitzer Space Telescope Infrared Spectrograph/MIPS data and similar ages. Both samples include stars with sources with infrared spectral energy distributions that show evidence of multiple components. Over the range of stellar types considered, we obtain nearly the same characteristic dust temperatures (~190 K and ~60 K for the inner and outer dust components, respectively)\u2014slightly above the ice evaporation temperature for the inner belts. The warm inner dust temperature is readily explained if populations of small grains are being released by sublimation of ice from icy planetesimals. Evaporation of low-eccentricity icy bodies at ~150 K can deposit particles into an inner/warm belt, where the small grains are heated to T_(dust)~ 190 K. Alternatively, enhanced collisional processing of an asteroid belt-like system of parent planetesimals just interior to the snow line may account for the observed uniformity in dust temperature. The similarity in temperature of the warmer dust across our B8-K0 stellar sample strongly suggests that dust-producing planetesimals are not found at similar radial locations around all stars, but that dust production is favored at a characteristic temperature horizon.", "doi": "10.1088/2041-8205/730/2/L29", "issn": "2041-8205", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2011-04-01", "series_number": "2", "volume": "730", "issue": "2", "pages": "Art. No. L29" }, { "id": "authors:nf9a6-d1115", "collection": "authors", "collection_id": "nf9a6-d1115", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101026-121324478", "type": "article", "title": "C_(60) in Reflection Nebulae", "author": [ { "family_name": "Sellgren", "given_name": "Kris", "clpid": "Sellgren-K" }, { "family_name": "Werner", "given_name": "Michael W.", "clpid": "Werner-M-W" }, { "family_name": "Ingalls", "given_name": "James G.", "orcid": "0000-0003-4714-1364", "clpid": "Ingalls-J-G" }, { "family_name": "Smith", "given_name": "J. D. T.", "orcid": "0000-0003-1545-5078", "clpid": "Smith-J-D-T" }, { "family_name": "Carleton", "given_name": "T. M.", "clpid": "Carleton-T-M" }, { "family_name": "Joblin", "given_name": "Christine", "clpid": "Joblin-C" } ], "abstract": "The fullerene C_(60) has four infrared-active vibrational transitions at 7.0, 8.5, 17.4, and 18.9 \u03bcm. We have previously observed emission features at 17.4 and 18.9 \u03bcm in the reflection nebula NGC 7023 and demonstrated spatial correlations suggestive of a common origin. We now confirm our earlier identification of these features with C_(60) by detecting a third emission feature at 7.04 \u00b1 0.05 \u03bcm in NGC 7023. We also report the detection of these three C_(60) features in the reflection nebula NGC 2023. Our spectroscopic mapping of NGC 7023 shows that the 18.9 \u03bcm C_(60) feature peaks on the central star and that the 16.4 \u03bcm emission feature due to polycyclic aromatic hydrocarbons peaks between the star and a nearby photodissociation front. The observed features in NGC 7023 are consistent with emission from UV-excited gas-phase C_(60). We find that 0.1%-0.6% of interstellar carbon is in C_(60); this abundance is consistent with those from previous upper limits and possible fullerene detections in the interstellar medium (ISM). This is the first firm detection of neutral C_(60) in the ISM.", "doi": "10.1088/2041-8205/722/1/L54", "issn": "2041-8205", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2010-10-10", "series_number": "1", "volume": "722", "issue": "1", "pages": "L54-L57" }, { "id": "authors:mxv0n-5vk89", "collection": "authors", "collection_id": "mxv0n-5vk89", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100317-112723473", "type": "article", "title": "The Collimation and Energetics of the Brightest Swift Gamma-ray Bursts", "author": [ { "family_name": "Cenko", "given_name": "S. B.", "orcid": "0000-0003-1673-970X", "clpid": "Cenko-S-B" }, { "family_name": "Frail", "given_name": "D. A.", "clpid": "Frail-D-A" }, { "family_name": "Harrison", "given_name": "F. A.", "orcid": "0000-0002-4226-8959", "clpid": "Harrison-F-A" }, { "family_name": "Kulkarni", "given_name": "S. R.", "orcid": "0000-0001-5390-8563", "clpid": "Kulkarni-S-R" }, { "family_name": "Nakar", "given_name": "E.", "orcid": "0000-0002-4534-7089", "clpid": "Nakar-E" }, { "family_name": "Chandra", "given_name": "P. C.", "clpid": "Chandra-P-C" }, { "family_name": "Butler", "given_name": "N. R.", "clpid": "Butler-N-R" }, { "family_name": "Fox", "given_name": "D. B.", "orcid": "0000-0002-3714-672X", "clpid": "Fox-D-B" }, { "family_name": "Gal-Yam", "given_name": "A.", "orcid": "0000-0002-3653-5598", "clpid": "Gal-Yam-A" }, { "family_name": "Kasliwal", "given_name": "M. M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Kelemen", "given_name": "J.", "clpid": "Kelemen-J" }, { "family_name": "Moon", "given_name": "D.-S.", "orcid": "0000-0003-4200-5064", "clpid": "Moon-Dae-Sik" }, { "family_name": "Ofek", "given_name": "E. O.", "orcid": "0000-0002-6786-8774", "clpid": "Ofek-E-O" }, { "family_name": "Price", "given_name": "P. A.", "clpid": "Price-P-A" }, { "family_name": "Rau", "given_name": "A.", "orcid": "0000-0001-5990-6243", "clpid": "Rau-A" }, { "family_name": "Soderberg", "given_name": "A. M.", "clpid": "Soderberg-A-M" }, { "family_name": "Teplitz", "given_name": "H. I.", "orcid": "0000-0002-7064-5424", "clpid": "Teplitz-H-I" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Bock", "given_name": "D. C.-J.", "clpid": "Bock-D-C-J" }, { "family_name": "Bloom", "given_name": "J. S.", "orcid": "0000-0002-7777-216X", "clpid": "Bloom-J-S" }, { "family_name": "Starr", "given_name": "D. A.", "clpid": "Starr-D-A" }, { "family_name": "Filippenko", "given_name": "A. V.", "orcid": "0000-0003-3460-0103", "clpid": "Filippenko-A-V" }, { "family_name": "Chevalier", "given_name": "R. A.", "clpid": "Chevalier-R-A" }, { "family_name": "Gehrels", "given_name": "N.", "clpid": "Gehrels-N" }, { "family_name": "Nousek", "given_name": "J. N.", "clpid": "Nousek-J-N" }, { "family_name": "Piran", "given_name": "T.", "orcid": "0000-0002-7964-5420", "clpid": "Piran-T" } ], "abstract": "Long-duration gamma-ray bursts (GRBs) are widely believed to be highly collimated explosions (bipolar conical outflows with half-opening angle \u03b8 \u2248 1\u00b0-10\u00b0). As a result of this beaming factor, the true energy release from a GRB is usually several orders of magnitude smaller than the observed isotropic value. Measuring this opening angle, typically inferred from an achromatic steepening in the afterglow light curve (a \"jet\" break), has proven exceedingly difficult in the Swift era. Here, we undertake a study of five of the brightest (in terms of the isotropic prompt \u03b3-ray energy release, E_(\u03b3,iso)) GRBs in the Swift era to search for jet breaks and hence constrain the collimation-corrected energy release. We present multi-wavelength (radio through X-ray) observations of GRBs 050820A, 060418, and 080319B, and construct afterglow models to extract the opening angle and beaming-corrected energy release for all three events. Together with results from previous analyses of GRBs 050904 and 070125, we find evidence for an achromatic jet break in all five events, strongly supporting the canonical picture of GRBs as collimated explosions. The most natural explanation for the lack of observed jet breaks from most Swift GRBs is therefore selection effects. However, the opening angles for the events in our sample are larger than would be expected if all GRBs had a canonical energy release of ~10^(51) erg. The total energy release we measure for the \"hyper-energetic\" (E_(tot) \u2273 10^(52) erg) events in our sample is large enough to start challenging models with a magnetar as the compact central remnant.", "doi": "10.1088/0004-637X/711/2/641", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2010-03-10", "series_number": "2", "volume": "711", "issue": "2", "pages": "641-654" }, { "id": "authors:jqf3m-ef285", "collection": "authors", "collection_id": "jqf3m-ef285", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091111-105736367", "type": "article", "title": "Planets and Debris Disks: Results from a Spitzer/MIPS Search for Infrared Excess", "author": [ { "family_name": "Bryden", "given_name": "G.", "clpid": "Bryden-G" }, { "family_name": "Beichman", "given_name": "C. A.", "orcid": "0000-0002-5627-5471", "clpid": "Beichman-C-A" }, { "family_name": "Carpenter", "given_name": "J. M.", "orcid": "0000-0003-2251-0602", "clpid": "Carpenter-J-M" }, { "family_name": "Rieke", "given_name": "G. H.", "orcid": "0000-0003-2303-6519", "clpid": "Rieke-G-H" }, { "family_name": "Stapelfeldt", "given_name": "K. R.", "orcid": "0000-0002-2805-7338", "clpid": "Stapelfeldt-K-R" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Tanner", "given_name": "A. M.", "orcid": "0000-0002-2903-2140", "clpid": "Tanner-A-M" }, { "family_name": "Lawler", "given_name": "S. M.", "orcid": "0000-0001-5368-386X", "clpid": "Lawler-S-M" }, { "family_name": "Wyatt", "given_name": "M. C.", "clpid": "Wyatt-M-C" }, { "family_name": "Trilling", "given_name": "D. E.", "orcid": "0000-0003-4580-3790", "clpid": "Trilling-D-E" }, { "family_name": "Su", "given_name": "K. Y. L.", "orcid": "0000-0002-3532-5580", "clpid": "Su-Katherine-Y-L" }, { "family_name": "Blaylock", "given_name": "M.", "clpid": "Blaylock-M" }, { "family_name": "Stansberry", "given_name": "J. A.", "clpid": "Stansberry-J-A" } ], "abstract": "Using the MIPS camera on the Spitzer Space Telescope, we have searched for debris disks around 104 stars known from radial velocity studies to have one or more planets. Combining this new data with 42 already published observations of planet-bearing stars, we find that 14 of the 146 systems have IR excess at 24 and/or 70 \u03bcm. Only one star, HD 69830, has IR excess exclusively at 24 \u03bcm, indicative of warm dust in the inner system analogous to that produced by collisions in the solar system's asteroid belt. For the other 13 stars with IR excess the emission is stronger at 70 \u03bcm, consistent with cool dust (<100 K) located beyond 10 AU, well outside of the orbital location of the known planets. Selection effects inhibit detection of faint disks around the planet-bearing stars (e.g., the stars tend to be more distant), resulting in a lower detection rate for IR excess than in a corresponding control sample of nearby stars not known to have planets (9% \u00b1 3% versus 14% \u00b1 3%). Even taking into account the selection bias, we find that the difference between the dust emission around stars with planets and stars without known planets is not statistically significant.", "doi": "10.1088/0004-637X/705/2/1226", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2009-11-10", "series_number": "2", "volume": "705", "issue": "2", "pages": "1226-1236" }, { "id": "authors:nd5xy-zd376", "collection": "authors", "collection_id": "nd5xy-zd376", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090827-090356504", "type": "article", "title": "Spitzer Mid-IR Spectra of Dust Debris Around A and Late B Type Stars: Asteroid Belt Analogs and Power-Law Dust Distributions", "author": [ { "family_name": "Morales", "given_name": "Farisa Y.", "orcid": "0000-0001-9414-3851", "clpid": "Morales-F-Y" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Bryden", "given_name": "G.", "clpid": "Bryden-G" }, { "family_name": "Plavchan", "given_name": "P.", "orcid": "0000-0002-8864-1667", "clpid": "Plavchan-P" }, { "family_name": "Stapelfeldt", "given_name": "K. R.", "orcid": "0000-0002-2805-7338", "clpid": "Stapelfeldt-K-R" }, { "family_name": "Rieke", "given_name": "G. H.", "orcid": "0000-0003-2303-6519", "clpid": "Rieke-G-H" }, { "family_name": "Su", "given_name": "K. Y. L.", "orcid": "0000-0002-3532-5580", "clpid": "Su-Katherine-Y-L" }, { "family_name": "Beichman", "given_name": "C. A.", "orcid": "0000-0002-5627-5471", "clpid": "Beichman-C-A" }, { "family_name": "Chen", "given_name": "C. H.", "orcid": "0000-0002-8382-0447", "clpid": "Chen-Christine-H" }, { "family_name": "Grogan", "given_name": "K.", "clpid": "Grogan-K" }, { "family_name": "Kenyon", "given_name": "S. J.", "orcid": "0000-0003-0214-609X", "clpid": "Kenyon-S-J" }, { "family_name": "Moro-Mart\u00edn", "given_name": "A.", "orcid": "0000-0001-9504-8426", "clpid": "Moro-Mart\u00edn-A" }, { "family_name": "Wolf", "given_name": "S.", "clpid": "Wolf-S" } ], "abstract": "Using the Spitzer/Infrared Spectrograph (IRS) low-resolution modules covering wavelengths from 5 to 35 \u03bcm, we observed 52 main-sequence A and late B type stars previously seen using Spitzer/Multiband Imaging Photometer (MIPS) to have excess infrared emission at 24 \u03bcm above that expected from the stellar photosphere. The mid-IR excess is confirmed in all cases but two. While prominent spectral features are not evident in any of the spectra, we observed a striking diversity in the overall shape of the spectral energy distributions. Most of the IRS excess spectra are consistent with single-temperature blackbody emission, suggestive of dust located at a single orbital radius\u2014a narrow ring. Assuming the excess emission originates from a population of large blackbody grains, dust temperatures range from 70 to 324 K, with a median of 190 K corresponding to a distance of 10 AU. Thirteen stars however, have dust emission that follows a power-law distribution, F_\u03bd = F 0\u03bb^\u03b1, with exponent \u03b1 ranging from 1.0 to 2.9. The warm dust in these systems must span a greater range of orbital locations\u2014an extended disk. All of the stars have also been observed with Spitzer/MIPS at 70 \u03bcm, with 27 of the 50 excess sources detected (signal-to-noise ratio > 3). Most 70 \u03bcm fluxes are suggestive of a cooler, Kuiper Belt-like component that may be completely independent of the asteroid belt-like warm emission detected at the IRS wavelengths. Fourteen of 37 sources with blackbody-like fits are detected at 70 \u03bcm. The 13 objects with IRS excess emission fit by a power-law disk model, however, are all detected at 70 \u03bcm (four above, three on, and six below the extrapolated power law), suggesting that the mid-IR IRS emission and far-IR 70 \u03bcm emission may be related for these sources. Overall, the observed blackbody and power-law thermal profiles reveal debris distributed in a wide variety of radial structures that do not appear to be correlated with spectral type or stellar age. An additional 43 fainter A and late B type stars without 70 \u03bcm photometry were also observed with Spitzer/IRS; results are summarized in Appendix B.", "doi": "10.1088/0004-637X/699/2/1067", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2009-07-10", "series_number": "2", "volume": "699", "issue": "2", "pages": "1067-1086" }, { "id": "authors:5jdy6-t0x58", "collection": "authors", "collection_id": "5jdy6-t0x58", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090917-111058624", "type": "article", "title": "New Debris Disks Around Young, Low-Mass Stars Discovered with the Spitzer Space Telescope", "author": [ { "family_name": "Plavchan", "given_name": "Peter", "orcid": "0000-0002-8864-1667", "clpid": "Plavchan-P" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Chen", "given_name": "C. H.", "orcid": "0000-0002-8382-0447", "clpid": "Chen-Christine-H" }, { "family_name": "Stapelfeldt", "given_name": "K. R.", "orcid": "0000-0002-2805-7338", "clpid": "Stapelfeldt-K-R" }, { "family_name": "Su", "given_name": "K. Y. L.", "orcid": "0000-0002-3532-5580", "clpid": "Su-Katherine-Y-L" }, { "family_name": "Stauffer", "given_name": "J. R.", "orcid": "0000-0003-3595-7382", "clpid": "Stauffer-J-R" }, { "family_name": "Song", "given_name": "I.", "orcid": "0000-0002-5815-7372", "clpid": "Song-Inseok" } ], "abstract": "We present 24 \u03bcm and 70 \u03bcm Multiband Imaging Photometer for Spitzer (MIPS) observations of 70 A through M-type dwarfs with estimated ages from 8 Myr to 1.1 Gyr, as part of a Spitzer guaranteed time program, including a re-analysis of some previously published source photometry. Our sample is selected from stars with common youth indicators such as lithium abundance, X-ray activity, chromospheric activity, and rapid rotation. We compare our MIPS observations to empirically derived K_s -[24] colors as a function of the stellar effective temperature to identify 24 \u03bcm and 70 \u03bcm excesses. We place constraints or upper limits on dust temperatures and fractional infrared luminosities with a simple blackbody dust model. We confirm the previously published 70 \u03bcm excesses for HD 92945, HD 112429, and AU Mic, and provide updated flux density measurements for these sources. We present the discovery of 70 \u03bcm excesses for five stars: HD 7590, HD 10008, HD 59967, HD 73350, and HD 135599. HD 135599 is also a known Spitzer IRS (InfraRed Spectrograph) excess source, and we confirm the excess at 24 \u03bcm. We also present the detection of 24 \u03bcm excesses for 10 stars: HD 10008, GJ 3400A, HD 73350, HD 112429, HD 123998, HD 175742, AT Mic, BO Mic, HD 358623 and Gl 907.1. We find that large 70 \u03bcm excesses are less common around stars with effective temperatures of less than 5000 K (3.7^(+7.6)_(\u20131.1)%) than around stars with effective temperatures between 5000 K and 6000 K (21.4^(+9.5)_(\u20135.7)%), despite the cooler stars having a younger median age in our sample (12 Myr vs. 340 Myr). We find that the previously reported excess for TWA 13A at 70 \u03bcm is due to a nearby background galaxy, and the previously reported excess for HD 177724 is due to saturation of the near-infrared photometry used to predict the mid-infrared stellar flux contribution. In the Appendix, we present an updated analysis of dust grain removal timescales due to grain-grain collisions and radiation pressure, Poynting-Robertson (P-R) drag, stellar wind drag, and planet-dust dynamical interaction. We find that drag forces can be important for disk dynamics relative to grain-grain collisions for L_(IR)/L_* < 10^(\u20134), and that stellar wind drag is more important than P-R drag for K and M dwarfs, and possibly for young (<1 Gyr) G dwarfs as well.", "doi": "10.1088/0004-637X/698/2/1068", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2009-06-20", "series_number": "2", "volume": "698", "issue": "2", "pages": "1068-1094" }, { "id": "authors:87qfh-wp985", "collection": "authors", "collection_id": "87qfh-wp985", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090806-093433828", "type": "article", "title": "Epsilon Eridani's planetary debris disk: structure and dynamics based on Spitzer and Caltech submillimeter observatory observations", "author": [ { "family_name": "Backman", "given_name": "D.", "clpid": "Backman-D-E" }, { "family_name": "Marengo", "given_name": "M.", "orcid": "0000-0001-9910-9230", "clpid": "Marengo-M" }, { "family_name": "Stapelfeldt", "given_name": "K.", "orcid": "0000-0002-2805-7338", "clpid": "Stapelfeldt-K-R" }, { "family_name": "Su", "given_name": "K. Y. L.", "orcid": "0000-0002-3532-5580", "clpid": "Su-Katherine-Y-L" }, { "family_name": "Wilner", "given_name": "D.", "orcid": "0000-0003-1526-7587", "clpid": "Wilner-D-J" }, { "family_name": "Dowell", "given_name": "C. D.", "clpid": "Dowell-C-D" }, { "family_name": "Watson", "given_name": "D.", "clpid": "Watson-D" }, { "family_name": "Stansberry", "given_name": "J.", "clpid": "Stansberry-J-A" }, { "family_name": "Rieke", "given_name": "G.", "orcid": "0000-0003-2303-6519", "clpid": "Rieke-G-H" }, { "family_name": "Megeath", "given_name": "T.", "orcid": "0000-0001-7629-3573", "clpid": "Megeath-S-T" }, { "family_name": "Fazio", "given_name": "G.", "orcid": "0000-0002-0670-0708", "clpid": "Fazio-G-G" }, { "family_name": "Werner", "given_name": "M.", "clpid": "Werner-M-W" } ], "abstract": "Spitzer and Caltech Submillimeter Observatory images and spectrophotometry of Eridani at wavelengths from 3.5 to 350 \u03bcm reveal new details of its bright debris disk. The 350 \u03bcm map confirms the presence of a ring at r = 11\"-28\"(35-90 AU), observed previously at longer sub-mm wavelengths. The Spitzer mid-IR and far-IR images do not show the ring, but rather a featureless disk extending from within a few arcsec of the star across the ring to r~ 34\" (110 AU). The spectral energy distribution (SED) of the debris system implies a complex structure. A model constrained by the surface brightness profiles and the SED indicates that the sub-mm ring emission is primarily from large (a~ 135 \u03bcm) grains, with smaller (a~ 15 \u03bcm) grains also present in and beyond the ring. The Spitzer Infrared Spectrograph and Multiband Imaging Photometer for Spitzer SED-mode spectrophotometry data clearly show the presence of spatially compact excess emission at \u03bb \u2273 15 \u03bcm that requires the presence of two additional narrow belts of dust within the sub-mm ring's central void. The innermost belt at r~ 3 AU is composed of silicate dust. A simple dynamical model suggests that dust produced collisionally by a population of about 11 M_\u2295 of planetesimals in the sub-mm ring could be the source of the emission from both in and beyond the sub-mm ring. Maintaining the inner belts and the inner edge to the sub-mm ring may require the presence of three planets in this system including the candidate radial velocity object.", "doi": "10.1088/0004-637X/690/2/1522", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2009-01-10", "series_number": "2", "volume": "690", "issue": "2", "pages": "1522-1538" }, { "id": "authors:wtke7-xvm68", "collection": "authors", "collection_id": "wtke7-xvm68", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:STUapj08", "type": "article", "title": "Spitzer and HHT observations of Bok globule B335: isolated star formation efficiency and cloud structure", "author": [ { "family_name": "Stutz", "given_name": "Amelia M.", "orcid": "0000-0003-2300-8200", "clpid": "Stutz-A-M" }, { "family_name": "Rubin", "given_name": "Mark", "clpid": "Rubin-M" }, { "family_name": "Werner", "given_name": "Michael W.", "clpid": "Werner-M-W" }, { "family_name": "Rieke", "given_name": "George H.", "orcid": "0000-0003-2303-6519", "clpid": "Rieke-G-H" }, { "family_name": "Bieging", "given_name": "John H.", "clpid": "Bieging-J-H" }, { "family_name": "Keene", "given_name": "Jocelyn", "clpid": "Keene-Jocelyn" }, { "family_name": "Kang", "given_name": "Miju", "orcid": "0000-0002-5016-050X", "clpid": "Kang-Miju" }, { "family_name": "Shirley", "given_name": "Yancy L.", "clpid": "Shirley-Y-L" }, { "family_name": "Su", "given_name": "K. Y. L.", "orcid": "0000-0002-3532-5580", "clpid": "Su-Katherine-Y-L" }, { "family_name": "Velusamy", "given_name": "Thangasamy", "clpid": "Velusamy-T" }, { "family_name": "Wilner", "given_name": "David J.", "orcid": "0000-0003-1526-7587", "clpid": "Wilner-D-J" } ], "abstract": "We present infrared and millimeter observations of Barnard 335, the prototypical isolated Bok globule with an embedded protostar. Using Spitzer data we measure the source luminosity accurately; we also constrain the density profile of the innermost globule material near the protostar using the observation of an 8.0 \u03bcm shadow. Heinrich Hertz Telescope (HHT) observations of ^12CO2-1 confirm the detection of a flattened molecular core with diameter ~10,000 AU and the same orientation as the circumstellar disk (~100 to 200 AU in diameter). This structure is probably the same as that generating the 8.0 mu m shadow and is expected from theoretical simulations of collapsing embedded protostars. We estimate the mass of the protostar to be only ~5% of the mass of the parent globule.", "doi": "10.1086/591789", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2008-11-01", "series_number": "1", "volume": "687", "issue": "1", "pages": "389-405" }, { "id": "authors:6pk3b-hr310", "collection": "authors", "collection_id": "6pk3b-hr310", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090517-192613736", "type": "article", "title": "Spitzer MIPS observations of stars in the \u03b2 Pictoris moving group", "author": [ { "family_name": "Rebull", "given_name": "L. M.", "orcid": "0000-0001-6381-515X", "clpid": "Rebull-L-M" }, { "family_name": "Stapelfeldt", "given_name": "K. R.", "orcid": "0000-0002-2805-7338", "clpid": "Stapelfeldt-K-R" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Mannings", "given_name": "V. G.", "clpid": "Mannings-V-G" }, { "family_name": "Chen", "given_name": "C.", "clpid": "Chen-C" }, { "family_name": "Stauffer", "given_name": "J. R.", "orcid": "0000-0003-3595-7382", "clpid": "Stauffer-J-R" }, { "family_name": "Smith", "given_name": "P. S.", "clpid": "Smith-P-S" }, { "family_name": "Song", "given_name": "I.", "orcid": "0000-0002-5815-7372", "clpid": "Song-Inseok" }, { "family_name": "Hines", "given_name": "D.", "orcid": "0000-0003-4653-6161", "clpid": "Hines-D-C" }, { "family_name": "Low", "given_name": "F. J.", "clpid": "Low-F-J" } ], "abstract": "We present Multiband Imaging Photometer for Spitzer (MIPS) observations at 24 and 70 \u03bcm for 30 stars, and at 160 \u03bcm for a subset of 12 stars, in the nearby (~30 pc), young (~12 Myr) \u03b2 Pictoris moving group (BPMG). In several cases, the new MIPS measurements resolve source confusion and background contamination issues in the IRAS data for this sample. We find that 7 members have 24 \u03bcm excesses, implying a debris disk fraction of 23%, and that at least 11 have 70 \u03bcm excesses (disk fraction of \u226537%). Five disks are detected at 160 \u03bcm (out of a biased sample of 12 stars observed), with a range of 160/70 flux ratios. The disk fraction at 24 and 70 \u03bcm, and the size of the excesses measured at each wavelength, are both consistent with an \"inside-out\" infrared excess decrease with time, wherein the shorter wavelength excesses disappear before longer wavelength excesses, and consistent with the overall decrease of infrared excess frequency with stellar age, as seen in Spitzer studies of other young stellar groups. Assuming that the infrared excesses are entirely due to circumstellar disks, we characterize the disk properties using simple models and fractional infrared luminosities. Optically thick disks, seen in the younger TW Hya and \u03b7 Cha associations, are entirely absent in the BPMG. Additional flux density measurements at 24 and 70 \u03bcm are reported for nine Tucana-Horologium association member stars. Since this is <20% of the association membership, limited analysis on the complete disk fraction of this association is possible.", "doi": "10.1086/588182", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2008-07-10", "series_number": "2", "volume": "681", "issue": "2", "pages": "1484-1504" }, { "id": "authors:ttqnq-w9483", "collection": "authors", "collection_id": "ttqnq-w9483", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090731-090808353", "type": "article", "title": "Spitzer Sage Survey of the Large Magellanic Cloud. III. Star Formation and ~1000 New Candidate Young Stellar Objects", "author": [ { "family_name": "Whitney", "given_name": "B. A.", "clpid": "Whitney-B-A" }, { "family_name": "Sewilo", "given_name": "M.", "orcid": "0000-0003-2248-6032", "clpid": "Sewilo-M" }, { "family_name": "Indebetouw", "given_name": "R.", "clpid": "Indebetouw-R" }, { "family_name": "Robitaille", "given_name": "T. P.", "orcid": "0000-0002-8642-1329", "clpid": "Robitaille-T-P" }, { "family_name": "Meixner", "given_name": "M.", "clpid": "Meixner-M" }, { "family_name": "Gordon", "given_name": "K.", "clpid": "Gordon-K-D" }, { "family_name": "Meade", "given_name": "M. R.", "clpid": "Meade-M-R" }, { "family_name": "Babler", "given_name": "B. L.", "clpid": "Babler-B-L" }, { "family_name": "Harris", "given_name": "J.", "clpid": "Harris-J" }, { "family_name": "Hora", "given_name": "J. L.", "orcid": "0000-0002-5599-4650", "clpid": "Hora-J-L" }, { "family_name": "Bracker", "given_name": "S.", "clpid": "Bracker-S" }, { "family_name": "Povich", "given_name": "M. S.", "orcid": "0000-0001-9062-3583", "clpid": "Povich-M-S" }, { "family_name": "Churchwell", "given_name": "E. B.", "clpid": "Churchwell-E-B" }, { "family_name": "Engelbracht", "given_name": "C. W.", "clpid": "Engelbracht-C-W" }, { "family_name": "For", "given_name": "B.-Q.", "clpid": "For-Bi-Qing" }, { "family_name": "Block", "given_name": "M.", "clpid": "Block-M" }, { "family_name": "Misselt", "given_name": "K.", "clpid": "Misselt-K" }, { "family_name": "Vijh", "given_name": "U.", "clpid": "Vijh-U" }, { "family_name": "Leitherer", "given_name": "C.", "orcid": "0000-0003-2685-4488", "clpid": "Leitherer-C" }, { "family_name": "Kawamura", "given_name": "A.", "clpid": "Kawamura-Akiko" }, { "family_name": "Blum", "given_name": "R. D.", "clpid": "Blum-R-D" }, { "family_name": "Cohen", "given_name": "M.", "clpid": "Cohen-Michael" }, { "family_name": "Fukui", "given_name": "Y.", "clpid": "Fukui-Yasuo" }, { "family_name": "Mizuno", "given_name": "A.", "clpid": "Mizuno-Akira" }, { "family_name": "Mizuno", "given_name": "N.", "clpid": "Mizuno-Norikazu" }, { "family_name": "Srinivasan", "given_name": "S.", "clpid": "Srinivasan-S" }, { "family_name": "Tielens", "given_name": "A. G. G. M.", "clpid": "Tielens-A-G-G-M" }, { "family_name": "Volk", "given_name": "K.", "clpid": "Volk-K" }, { "family_name": "Bernard", "given_name": "J. P.", "clpid": "Bernard-J-P" }, { "family_name": "Boulanger", "given_name": "F.", "clpid": "Boulanger-F" }, { "family_name": "Frogel", "given_name": "J. A.", "clpid": "Frogel-J-A" }, { "family_name": "Gallagher", "given_name": "J.", "clpid": "Gallagher-J" }, { "family_name": "Gorjian", "given_name": "V.", "clpid": "Gorjian-V" }, { "family_name": "Kelly", "given_name": "D.", "clpid": "Kelly-D" }, { "family_name": "Latter", "given_name": "W. B.", "clpid": "Latter-W-B" }, { "family_name": "Madden", "given_name": "S.", "clpid": "Madden-S" }, { "family_name": "Kemper", "given_name": "F.", "clpid": "Kemper-F" }, { "family_name": "Mould", "given_name": "J. R.", "orcid": "0000-0003-3820-1740", "clpid": "Mould-J-R" }, { "family_name": "Nota", "given_name": "A.", "clpid": "Nota-A" }, { "family_name": "Oey", "given_name": "M. S.", "clpid": "Oey-M-S" }, { "family_name": "Olsen", "given_name": "K. A.", "orcid": "0000-0002-7134-8296", "clpid": "Olsen-Knut-A-G" }, { "family_name": "Onishi", "given_name": "T.", "clpid": "Onishi-Toshikazu" }, { "family_name": "Paladini", "given_name": "R.", "orcid": "0000-0002-5158-243X", "clpid": "Paladini-Roberta" }, { "family_name": "Panagia", "given_name": "N.", "clpid": "Panagia-N" }, { "family_name": "Perez-Gonzalez", "given_name": "P.", "clpid": "Perez-Gonzalez-P" }, { "family_name": "Reach", "given_name": "W.", "orcid": "0000-0001-8362-4094", "clpid": "Reach-W-T" }, { "family_name": "Shibai", "given_name": "H.", "clpid": "Shibai-Hiroshi" }, { "family_name": "Sato", "given_name": "S.", "clpid": "Sato-S" }, { "family_name": "Smith", "given_name": "L. J.", "orcid": "0000-0002-0806-168X", "clpid": "Smith-L-J" }, { "family_name": "Staveley-Smith", "given_name": "L.", "clpid": "Staveley-Smith-L" }, { "family_name": "Ueta", "given_name": "T.", "clpid": "Ueta-Toshiya" }, { "family_name": "van Dyk", "given_name": "S. D.", "orcid": "0000-0001-9038-9950", "clpid": "Van-Dyk-S-D" }, { "family_name": "Werner", "given_name": "M.", "clpid": "Werner-M-W" }, { "family_name": "Wolff", "given_name": "M.", "orcid": "0000-0002-4013-5650", "clpid": "Wolff-M-T" }, { "family_name": "Zaritsky", "given_name": "D.", "orcid": "0000-0002-5177-727X", "clpid": "Zaritsky-D" } ], "abstract": "We present ~1000 new candidate Young Stellar Objects (YSOs) in the Large Magellanic Cloud selected from Spitzer Space Telescope data, as part of the Surveying the Agents of a Galaxy's Evolution (SAGE) Legacy program. The YSOs, detected by their excess infrared (IR) emission, represent early stages of evolution, still surrounded by disks and/or infalling envelopes. Previously, fewer than 20 such YSOs were known. The candidate YSOs were selected from the SAGE Point Source Catalog from regions of color-magnitude space least confused with other IR-bright populations. The YSOs are biased toward intermediate- to high-mass and young evolutionary stages, because these overlap less with galaxies and evolved stars in color-magnitude space. The YSOs are highly correlated spatially with atomic and molecular gas, and are preferentially located in the shells and bubbles created by massive stars inside. They are more clustered than generic point sources, as expected if star formation occurs in filamentary clouds or shells. We applied a more stringent color-magnitude selection to produce a subset of \"high-probability\" YSO candidates. We fitted the spectral-energy distributions (SEDs) of this subset and derived physical properties for those that were well fitted. The total mass of these well-fitted YSOs is ~2900 M_\u2609 and the total luminosity is ~2.1 \u00d7 10^6 L_\u2609 . By extrapolating the mass function with a standard initial mass function and integrating, we calculate a current star-formation rate of ~0.06 M_\u2609 yr^(\u20131), which is at the low end of estimates based on total ultraviolet and IR flux from the galaxy (~0.05 \u2013 0.25 M_\u2609 yr^(\u20131)), consistent with the expectation that our current YSO list is incomplete. Follow-up spectroscopy and further data mining will better separate the different IR-bright populations and likely increase the estimated number of YSOs. The full YSO list is available as electronic tables, and the SEDs are available as an electronic figure for further use by the scientific community.", "doi": "10.1088/0004-6256/136/1/18", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2008-07", "series_number": "1", "volume": "136", "issue": "1", "pages": "18-43" }, { "id": "authors:968cw-31q09", "collection": "authors", "collection_id": "968cw-31q09", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100113-090857631", "type": "article", "title": "Discovery of Two T Dwarf Companions with the Spitzer Space Telescope", "author": [ { "family_name": "Luhman", "given_name": "K. L.", "clpid": "Luhman-K-L" }, { "family_name": "Patten", "given_name": "B. M.", "clpid": "Patten-B-M" }, { "family_name": "Marengo", "given_name": "M.", "orcid": "0000-0001-9910-9230", "clpid": "Marengo-M" }, { "family_name": "Schuster", "given_name": "M. T.", "clpid": "Schuster-M-T" }, { "family_name": "Hora", "given_name": "J. L.", "orcid": "0000-0002-5599-4650", "clpid": "Hora-J-L" }, { "family_name": "Ellis", "given_name": "R. G.", "clpid": "Ellis-R-G" }, { "family_name": "Stauffer", "given_name": "J. R.", "orcid": "0000-0003-3595-7382", "clpid": "Stauffer-J-R" }, { "family_name": "Sonnett", "given_name": "S. M.", "orcid": "0000-0003-2762-8909", "clpid": "Sonnett-S-M" }, { "family_name": "Winston", "given_name": "E.", "clpid": "Winston-E" }, { "family_name": "Gutermuth", "given_name": "R. A.", "orcid": "0000-0002-6447-899X", "clpid": "Gutermuth-R-A" }, { "family_name": "Megeath", "given_name": "S. T.", "orcid": "0000-0001-7629-3573", "clpid": "Megeath-S-T" }, { "family_name": "Backman", "given_name": "D. E.", "clpid": "Backman-D-E" }, { "family_name": "Henry", "given_name": "T. J.", "clpid": "Henry-T-J" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Fazio", "given_name": "G. G.", "orcid": "0000-0002-0670-0708", "clpid": "Fazio-G-G" } ], "abstract": "We report the discovery of T dwarf companions to the nearby stars HN Peg (G0 V, 18.4 pc, \u03c4 ~ 0.3 Gyr) and HD 3651 (K0 V, 11.1 pc, \u03c4 ~ 7 Gyr). During an ongoing survey of 5' \u00d7 5' fields surrounding stars in the solar neighborhood with the Infrared Array Camera aboard the Spitzer Space Telescope, we identified these companions as candidate T dwarfs based on their mid-infrared colors. Using near-infrared spectra obtained with SpeX at the NASA Infrared Telescope Facility, we confirm the presence of methane absorption that characterizes T dwarfs and measure spectral types of T2.5 \u00b1 0.5 and T7.5 \u00b1 0.5 for HN Peg B and HD 3651B, respectively. By comparing our Spitzer data to images from the Two Micron All Sky Survey obtained several years earlier, we find that the proper motions of HN Peg B and HD 3651B are consistent with those of the primaries, confirming their companionship. A comparison of their luminosities to the values predicted by theoretical evolutionary models implies masses of 0.021 \u00b1 0.009 and 0.051 \u00b1 0.014 M_\u2299 for HN Peg B and HD 3651B, respectively. In addition, the models imply an effective temperature for HN Peg B that is significantly lower than the values derived for other T dwarfs at similar spectral types, which is the same behavior reported by Metchev & Hillenbrand for the young late L dwarf HD 203030B. Thus, the temperature of the L/T transition appears to depend on surface gravity. Meanwhile, HD 3651B is the first substellar companion directly imaged around a star that is known to harbor a close-in planet from radial velocity surveys. The discovery of this companion supports the notion that the high eccentricities of close-in planets like that near HD 3651 may be the result of perturbations by low-mass companions at wide separations.", "doi": "10.1086/509073", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2007-01-01", "series_number": "1", "volume": "654", "issue": "1", "pages": "570-579" }, { "id": "authors:pkpt8-e6k18", "collection": "authors", "collection_id": "pkpt8-e6k18", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:GEHrsi07", "type": "article", "title": "The NASA Spitzer Space Telescope", "author": [ { "family_name": "Gehrz", "given_name": "R. D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "Roellig", "given_name": "T. L.", "clpid": "Roellig-T-L" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Fazio", "given_name": "G. G.", "orcid": "0000-0002-0670-0708", "clpid": "Fazio-G-G" }, { "family_name": "Houck", "given_name": "J. R.", "clpid": "Houck-J-R" }, { "family_name": "Low", "given_name": "F. J.", "clpid": "Low-F-J" }, { "family_name": "Rieke", "given_name": "G. H.", "orcid": "0000-0003-2303-6519", "clpid": "Rieke-G-H" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Levine", "given_name": "D. A.", "clpid": "Levine-D-A" }, { "family_name": "Romana", "given_name": "E. A.", "clpid": "Romana-E-A" } ], "abstract": "The National Aeronautics and Space Administration's Spitzer Space Telescope (formerly the Space Infrared Telescope Facility) is the fourth and final facility in the Great Observatories Program, joining Hubble Space Telescope (1990), the Compton Gamma-Ray Observatory (1991\u20132000), and the Chandra X-Ray Observatory (1999). Spitzer, with a sensitivity that is almost three orders of magnitude greater than that of any previous ground-based and space-based infrared observatory, is expected to revolutionize our understanding of the creation of the universe, the formation and evolution of primitive galaxies, the origin of stars and planets, and the chemical evolution of the universe. This review presents a brief overview of the scientific objectives and history of infrared astronomy. We discuss Spitzer's expected role in infrared astronomy for the new millennium. We describe pertinent details of the design, construction, launch, in-orbit checkout, and operations of the observatory and summarize some science highlights from the first two and a half years of Spitzer operations. More information about Spitzer can be found at http://spitzer.caltech.edu/.", "doi": "10.1063/1.2431313", "issn": "0034-6748", "publisher": "American Institute of Physics", "publication": "Review of Scientific Instruments", "publication_date": "2007-01", "series_number": "1", "volume": "78", "issue": "1", "pages": "Art. No. 011302" }, { "id": "authors:0k3te-cjj35", "collection": "authors", "collection_id": "0k3te-cjj35", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170223-081326326", "type": "article", "title": "The Compact Nucleus of the Deep Silicate Absorption Galaxy NGC 4418", "author": [ { "family_name": "Evans", "given_name": "A. S.", "orcid": "0000-0003-2638-1334", "clpid": "Evans-A-S" }, { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Scoville", "given_name": "N. Z.", "orcid": "0000-0002-0438-3323", "clpid": "Scoville-N-Z" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Matthews", "given_name": "K.", "clpid": "Matthews-Keith-Astronomy" }, { "family_name": "Ressler", "given_name": "M.", "clpid": "Ressler-M-E" }, { "family_name": "Werner", "given_name": "M.", "clpid": "Werner-M-W" }, { "family_name": "Rieke", "given_name": "M.", "orcid": "0000-0002-7893-6170", "clpid": "Rieke-M-J" } ], "abstract": "High-resolution Hubble Space Telescope (HST) near-infrared and Keck mid-infrared images of the heavily extinguished infrared-luminous galaxy NGC 4418 are presented. These data make it possible to observe the imbedded near-infrared structure on scales of 10\u201320 pc and to constrain the size of the mid-infrared\u2013emitting region. The 1.1\u20132.2 \u03bcm data of NGC 4418 show no clear evidence of nuclear star clusters or of a reddened active galactic nucleus. Instead, the nucleus of the galaxy consists of a ~100\u2013200 pc linear structure with fainter structures extending radially outward. The near-infrared colors of the linear feature are consistent with a 10\u2013300 Myr starburst suffering moderate levels (a few magnitudes) of visual extinction. At 7.9\u201324.5 \u03bcm NGC 4418 has estimated size upper limits in the range of 30\u201380 pc. These dimensions are consistent with the highest-resolution radio observations obtained to date of NGC 4418, as well as the size of 50\u201370 pc expected for a blackbody with a temperature derived from the 25, 60, and 100 \u03bcm flux densities of the galaxy. Further, a spectral energy distribution constructed from the multiwavelength mid-infrared observations shows the strong silicate absorption feature at 10 \u03bcm, consistent with previous mid-infrared observations of NGC 4418. An infrared surface brightness of ~2.1 \u00d7 10^(13) L_\u2299 kpc^(-2) is derived for NGC 4418. Such a value, though consistent with the surface brightness of warm ultraluminous infrared galaxies [L_(IR)(8\u20131000 \u03bcm) \u2265 10^(12) L_\u2299], such as IRAS 05189-2524 and IRAS 08572+3915, is not large enough to distinguish NGC 4418 as a galaxy powered by an active galactic nucleus, as opposed to a lower surface brightness starburst.", "doi": "10.1086/374234", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2003-05", "series_number": "5", "volume": "125", "issue": "5", "pages": "2341-2347" }, { "id": "authors:ftsf2-c5v61", "collection": "authors", "collection_id": "ftsf2-c5v61", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170322-085802408", "type": "article", "title": "The SIRTF First-Look Survey. I. VLA Image and Source Catalog", "author": [ { "family_name": "Condon", "given_name": "J. J.", "orcid": "0000-0003-4724-1939", "clpid": "Condon-J-J" }, { "family_name": "Cotton", "given_name": "W. D.", "clpid": "Cotton-W-D" }, { "family_name": "Yin", "given_name": "Q.-F.", "clpid": "Yin-Q-F" }, { "family_name": "Shupe", "given_name": "D. L.", "orcid": "0000-0003-4401-0430", "clpid": "Shupe-David-L" }, { "family_name": "Storrie-Lombardi", "given_name": "L. J.", "orcid": "0000-0002-5987-5210", "clpid": "Storrie-Lombardi-L-J" }, { "family_name": "Helou", "given_name": "G.", "orcid": "0000-0003-3367-3415", "clpid": "Helou-G" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" } ], "abstract": "The First-Look Survey (FLS) of the Space Infrared Telescope Facility (SIRTF) will cover about 5 deg^2 centered on J2000.0 \u03b1 = 17^h18^m, \u03b4 = +59\u00b030' in order to characterize the extragalactic infrared sky 2 orders of magnitude deeper than the IRAS survey. We expect that most of the FLS far-infrared (\u03bb = 160, 70, and 24 \u03bcm) sources will be star-forming galaxies obeying the very tight far-infrared/radio correlation and will be continuum radio sources with flux densities S \u2273100 \u03bcJy at \u03bd = 1.4 GHz. Conversely, radio sources stronger than 100 \u03bcJy are usually powered by star-forming galaxies, plus some active galactic nuclei, and most should be detectable by the SIRTF FLS. Thus, a sensitive radio survey can be used to select and identify most of the SIRTF FLS source population before launch. We used the B configuration of the VLA to make an image of the FLS area at \u03bd = 1.4 GHz with \u03c3 \u2248 23 \u03bcJy beam^(-1) rms fluctuations, \u03b8 = 5.\"0 resolution, and \u03c3_\u03b1 \u2248 \u03c3\u03b4 \u227e0.\"5 rms uncertainties in right ascension and declination. The resulting radio image and catalog of 3565 radio components with peak flux densities S_p \u2265 5 \u03c3 = 115 \u03bcJy beam^(-1) have been released via the Web to expedite follow-up optical identification and spectroscopy.", "doi": "10.1086/374633", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2003-05", "series_number": "5", "volume": "125", "issue": "5", "pages": "2411-2426" }, { "id": "authors:nn2m8-cee25", "collection": "authors", "collection_id": "nn2m8-cee25", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170208-103123393", "type": "article", "title": "High Spatial Resolution Imaging of NGC 1068 in the Mid-Infrared", "author": [ { "family_name": "Bock", "given_name": "J. J.", "orcid": "0000-0002-5710-5212", "clpid": "Bock-J-J" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Matthews", "given_name": "K.", "clpid": "Matthews-K" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Ressler", "given_name": "M.", "clpid": "Ressler-M-E" }, { "family_name": "Marsh", "given_name": "K.", "orcid": "0000-0003-0107-7803", "clpid": "Marsh-K-A" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Egami", "given_name": "E.", "clpid": "Egami-Eichi" }, { "family_name": "Blandford", "given_name": "R.", "orcid": "0000-0002-1854-5506", "clpid": "Blandford-R-D" } ], "abstract": "Mid-infrared observations of the central source of NGC 1068 have been obtained with a spatial resolution in the deconvolved image of 0.\"1 (~7 pc). The central source is extended by ~1'' in the north-south direction but appears unresolved in the east-west direction over most of its length. About 2/3 of its flux can be ascribed to a core structure that is itself elongated north-south and does not show a distinct unresolved compact source. The source is strongly asymmetric, extending significantly farther to the north than to the south. The morphology of the mid-infrared emission appears similar to that of the radio jet and has features which correlate with the images in [O III]. Its 12.5\u201324.5 \u03bcm color temperature ranges from 215 to 260 K and does not decrease smoothly with distance from the core. Silicate absorption is strongest in the core and to the south and is small in the north. The core, apparently containing 2/3 of the bolometric luminosity of the inner 4'' diameter area, may be explained by a thick, dusty torus near the central active galactic nucleus (AGN) viewed at an angle of ~65\u00b0 to its plane. There are, however, detailed difficulties with existing models, especially the narrow east-west width of the thin extended mid-infrared \"tongue\" to the north of the core. We interpret the tongue as reprocessed visual and ultraviolet radiation that is strongly beamed and that originates in the AGN.", "doi": "10.1086/316871", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2000-12", "series_number": "6", "volume": "120", "issue": "6", "pages": "2904-2919" }, { "id": "authors:qvwsk-9w602", "collection": "authors", "collection_id": "qvwsk-9w602", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-111812339", "type": "article", "title": "High Resolution Mid-Infrared Imaging of Ultraluminous Infrared Galaxies", "author": [ { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Matthews", "given_name": "K.", "clpid": "Matthews-Keith-Astronomy" }, { "family_name": "Egami", "given_name": "E.", "clpid": "Egami-Eichi" }, { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Weinberger", "given_name": "A. J.", "orcid": "0000-0001-6654-7859", "clpid": "Weinberger-A-J" }, { "family_name": "Ressler", "given_name": "M.", "clpid": "Ressler-M-E" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Evans", "given_name": "A. S.", "orcid": "0000-0003-2638-1334", "clpid": "Evans-A-S" }, { "family_name": "Scoville", "given_name": "N. Z.", "orcid": "0000-0002-0438-3323", "clpid": "Scoville-N-Z" }, { "family_name": "Surace", "given_name": "J. A.", "orcid": "0000-0001-7291-0087", "clpid": "Surace-J-A" }, { "family_name": "Condon", "given_name": "J. J.", "orcid": "0000-0003-4724-1939", "clpid": "Condon-J-J" } ], "abstract": "Observations of ultraluminous infrared galaxies (ULIRGs) with an achieved resolution approaching the diffraction limit in the mid-infrared from 8 to 25 \u03bcm using the Keck Telescopes are reported. We find extremely compact structures, with spatial scales of less than 0.\"3 (diameter) in six of the seven ULIRGs observed. These compact sources emit between 30% and 100% of the mid-infrared energy from these galaxies. We have utilized the compact mid-infrared structures as a diagnostic of whether an AGN or a compact (100\u2013300 pc) starburst is the primary power source in these ULIRGs. In Markarian 231, the upper limit on the diameter of the 12.5 \u03bcm source, 0.\"13, shows that the size of the infrared source must increase with increasing wavelength, consistent with AGN models. In IRAS 05189-2524 and IRAS 08572+3915 there is strong evidence that the source size increases with increasing wavelength. This suggests heating by a central source rather than an extended luminosity source, consistent with the optical classification as an AGN. The compact mid-infrared sources seen in the other galaxies cannot be used to distinguish the ultimate luminosity source. If these ULIRGs are powered by compact starbursts, the star formation rates seen in the central few hundred parsecs far exceed the global rates seen in nearby starburst galaxies, and approach the surface brightness of individual clusters in nearby starburst galaxies.", "doi": "10.1086/301233", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2000-02", "series_number": "2", "volume": "119", "issue": "2", "pages": "509-523" }, { "id": "authors:4faw9-59896", "collection": "authors", "collection_id": "4faw9-59896", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-110545810", "type": "article", "title": "High Spatial Resolution Imaging of Arp 220 from 3 to 25 Microns", "author": [ { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Matthews", "given_name": "K.", "clpid": "Matthews-Keith-Astronomy" }, { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Ressler", "given_name": "M.", "clpid": "Ressler-M-E" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Weinberger", "given_name": "A. J.", "orcid": "0000-0001-6654-7859", "clpid": "Weinberger-A-J" }, { "family_name": "Egami", "given_name": "E.", "clpid": "Egami-Eichi" } ], "abstract": "Images of Arp 220 from 3.45 to 24.5 \u03bcm with 0farcs5 resolution are presented that clearly separate the nucleus into at least two components. The western component is about 3 times more luminous than the eastern component, but the silicate absorption in the fainter, eastern component is roughly 50% greater than the absorption in the western component. Each component is marginally resolved. The two components seen at 24.5 \u03bcm are identified with the two radio components. The western source most likely coincides with the high-extinction disk previously suggested to exist in Arp 220, while the eastern nucleus is identified with a faint, highly reddened source seen in HST 2.2 \u03bcm NICMOS images. The two nuclei together account for essentially all of the measured 24.5 \u03bcm flux density. Two models are presented, both of which fit the observations. In one the majority of the total luminosity is produced in an extended star formation region, and in the other most of the luminosity is produced in the compact but extincted regions associated with the two nuclei seen at 24.5 \u03bcm. In both pictures, substantial luminosity at 100 \u03bcm emerges from a component having a diameter of 2\"-3\" (~1 kpc).", "doi": "10.1086/306855", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "1999-03-01", "series_number": "1", "volume": "513", "issue": "1", "pages": "207-214" }, { "id": "authors:fabcj-n6p67", "collection": "authors", "collection_id": "fabcj-n6p67", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170228-083015431", "type": "article", "title": "Keck mid-IR High-Resolution Imaging of Arp 220", "author": [ { "family_name": "Egami", "given_name": "E.", "clpid": "Egami-Eichi" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Matthews", "given_name": "K.", "clpid": "Matthews-Keith-Astronomy" }, { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Weinberger", "given_name": "A. J.", "orcid": "0000-0001-6654-7859", "clpid": "Weinberger-A-J" }, { "family_name": "Ressler", "given_name": "M.", "clpid": "Ressler-M-E" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" } ], "abstract": "To identify the main power source of an object, it is necessary to obtain high-resolution images of that object at the wavelengths at which most of the luminosity is coming out. However, such observations had not been possible in the studies of ULIRGs, which release most of their luminosity in the mid/far-IR. High-resolution imaging at 25 \u00b5m, for example, requires not only a sensitive mid-IR camera but also a 10-m class telescope to achieve a sub-arcsecond difraction limit. Recently, such high-resolution imaging in the mid-IR has become possible with the MIRLIN mid-IR camera (Ressler 1994) on the Keck II telescope. This camera is based on a 128 x 128 Si:As array, and has a field of view of 17\" on a side with a pixel scale of 0.\"138/pixel. The working wavelength range is 5-26 \u00b5m. Using MIRLIN, we are now undertaking a program to perform high-resolution mid-IR imaging of nearby ultraluminous IR galaxies. Here, we present our first results on Arp 220. More details can be found in Soifer et al. (1999).", "doi": "10.1023/A:1002697514481", "issn": "0004-640X", "publisher": "Springer", "publication": "Astrophysics and Space Science", "publication_date": "1999-03", "series_number": "1/2", "volume": "266", "issue": "1/2", "pages": "109-111" }, { "id": "authors:10azh-m1d86", "collection": "authors", "collection_id": "10azh-m1d86", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170224-065459691", "type": "article", "title": "Hubble Space Telescope Imaging Polarimetry of the Gravitational Lens FSC 10214+4724", "author": [ { "family_name": "Nguyen", "given_name": "Hien T.", "clpid": "Nguyen-Hien-Trong" }, { "family_name": "Eisenhardt", "given_name": "Peter R.", "clpid": "Eisenhardt-P-R-M" }, { "family_name": "Werner", "given_name": "Michael W.", "clpid": "Werner-M-W" }, { "family_name": "Goodrich", "given_name": "Robert", "clpid": "Goodrich-R-W" }, { "family_name": "Hogg", "given_name": "David W.", "orcid": "0000-0003-2866-9403", "clpid": "Hogg-D-W" }, { "family_name": "Armus", "given_name": "Lee", "orcid": "0000-0003-3498-2973", "clpid": "Armus-L" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" } ], "abstract": "We present imaging polarimetry of the extremely luminous, redshift 2.3 IRAS source FSC 10214+4724. The observations were obtained with HST's Faint Object Camera in the F437M filter, which is free of strong emission lines. The 0farcs7 long arc is unresolved to 0farcs04 FWHM in the transverse direction and has an integrated polarization of 28% \u00b1 3%, in good agreement with ground-based observations. The polarization position angle varies along the arc by up to 35\u00b0. The overall position angle is 62\u00b0 \u00b1 3\u00b0 east of north. No counterimage is detected to B = 27.5 mag (3 \u03c3), giving an observed arc to counterimage flux ratio greater than 250, considerably greater than the flux ratio of 100 measured previously in the I band. This implies that the configuration of the object in the source plane at the B band is different from that at I band and/or that the lensing galaxy is dusty.", "doi": "10.1086/300742", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "1999-02", "series_number": "2", "volume": "117", "issue": "2", "pages": "671-676" }, { "id": "authors:paxyy-pmc30", "collection": "authors", "collection_id": "paxyy-pmc30", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170213-171516059", "type": "article", "title": "Hubble Space Telescope Observations of the Luminous IRAS Source FSC 10214+4724: A Gravitationally Lensed Infrared Quasar", "author": [ { "family_name": "Eisenhardt", "given_name": "Peter R.", "clpid": "Eisenhardt-P-R-M" }, { "family_name": "Armus", "given_name": "Lee", "orcid": "0000-0003-3498-2973", "clpid": "Armus-L" }, { "family_name": "Hogg", "given_name": "David W.", "orcid": "0000-0003-2866-9403", "clpid": "Hogg-D-W" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Werner", "given_name": "Michael W.", "clpid": "Werner-M-W" } ], "abstract": "With a redshift of 2.3, the IRAS source FSC 10214+4724 is apparently one of the most luminous objects known in the universe. We present an image of FSC 10214+4724 at 0.8 \u03bcm obtained with the Hubble Space Telescope (HST) WFPC2 Planetary Camera. The source appears as an unresolved ( < 0\".06) arc 0\".7 long, with significant substructure along its length. The center of curvature of the arc is located near an elliptical galaxy 1\".18 to the north. An unresolved component 100 times fainter than the arc is clearly detected on the opposite side of this galaxy. The most straightforward interpretation is that FSC 10214+4724 is gravitationally lensed by the foreground elliptical galaxy, with the faint component a counterimage of the IRAS source. The brightness of the arc in the HST image is then magnified by ~ 100, and the intrinsic source diameter is -0\".01 (80 pc) at 0.25 \u03bcm rest wavelength. The bolometric luminosity is probably amplified by a smaller factor ( ~ 30) as a result of the larger extent expected for the source in the far-infrared. A detailed lensing model is presented that reproduces the observed morphology and relative flux of the arc and counterimage and correctly predicts the position angle of the lensing galaxy. The model also predicts reasonable values for the velocity dispersion, mass, and mass-to-light ratio of the lensing galaxy for a wide range of galaxy redshifts. A redshift for the lensing galaxy of ~ 0.9 is consistent with the measured surface brightness profile from the image, as well as with the galaxy's spectral energy distribution. The background lensed source has an intrinsic luminosity ~ 2 x 10^(13) L_\u2299 and remains a highly luminous quasar with an extremely large ratio of infrared to optical/ultraviolet luminosity.", "doi": "10.1086/177038", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "1996-04-10", "series_number": "1", "volume": "461", "issue": "1", "pages": "72-83" }, { "id": "authors:bn1w4-m7v24", "collection": "authors", "collection_id": "bn1w4-m7v24", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140319-131640084", "type": "article", "title": "Extragalactic 1 millimeter sources: Simultaneous observations at centimeter, millimeter, and visual wavelengths", "author": [ { "family_name": "Landau", "given_name": "R.", "clpid": "Landau-R" }, { "family_name": "Jones", "given_name": "T. W.", "clpid": "Jones-T-W" }, { "family_name": "Epstein", "given_name": "E. E.", "clpid": "Epstein-E-E" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Puschell", "given_name": "J. J.", "clpid": "Puschell-J-J" }, { "family_name": "Balonek", "given_name": "T. J.", "clpid": "Balonek-T-J" } ], "abstract": "Observations simultaneously made at visual (B, V, and R) wavelengths, at 1, 1.4, and 3.4 mm and at 1.3, 2, 6, and 20 cm of 9 QSOs and BL Lac objects are reported. The range of the millimeter visual spectral index \u0251_(mv) was only 0.65-0.82, typical of optically thin synchrotron emission. This may indicate that the electrons radiating synchrotron emission in this portion of the spectrum are not subjected to large radiative losses, and therefore relativistic bulk motion with Doppler factors ~10 are required. The visual spectral index is much more broadly distributed and typically larger than \u0251_(mv). The spectral energy distributions have not changed much in the last 2-5 years except for 2251 + 15 and perhaps 0235 + 164. Only 1749 +09 shows a sharp spectral break shortward of 1 mm. Sixteen other sources were observed at 1 mm, of which seven were detected.", "doi": "10.1086/160930", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "1983-05-01", "series_number": "1", "volume": "268", "issue": "1", "pages": "68-75" }, { "id": "authors:zcptc-35249", "collection": "authors", "collection_id": "zcptc-35249", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170308-113011537", "type": "article", "title": "Temperatures of galactic molecular clouds showing CO self-absorption", "author": [ { "family_name": "Phillips", "given_name": "T. G.", "clpid": "Phillips-T-G" }, { "family_name": "Knapp", "given_name": "G. R.", "orcid": "0000-0002-9259-1164", "clpid": "Knapp-G-R" }, { "family_name": "Wannier", "given_name": "P. G.", "clpid": "Wannier-P-G" }, { "family_name": "Huggins", "given_name": "P. J.", "clpid": "Huggins-P-J" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Ennis", "given_name": "D.", "clpid": "Ennis-D" } ], "abstract": "The CO J=2- l line has been observed and, in most cases, mapped in 10 star-forming molecular clouds (W3, NGC 1333, NGC 2071, Mon R2, CRL 961, p Oph, W49N, W51A, DR 21, and Cep A). The CO J = 3-2 line has been observed in W3 and DR 21. The CO lines from all of these sources are strongly self-absorbed. By comparing our results with published CO (1-0) line profiles, we find that\nlarge corrections to the temperatures of the cloud cores, as measured by the CO (1-0) lines, are required. The corrections for self-absorption bring the CO brightness temperatures into closer agreement with the grain temperatures inferred from far-infrared photometry. The absorbing gas appears to have a variety of geometrical relationships with the absorbed\n'background' gas for this group of sources; in one or two cases there may be no physical connection between the absorbed and absorbing regions. For some CO sources, the combined CO data indicate the presence of velocity gradients; however, whether these are due to expansion or collapse cannot be decided on the basis of the presently available data.", "doi": "10.1086/158826", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "1981-04-15", "volume": "245", "pages": "512-528" }, { "id": "authors:zsjt6-er440", "collection": "authors", "collection_id": "zsjt6-er440", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170322-161717840", "type": "article", "title": "Infrared emission and star formation in the central regions of the galaxy IC 342", "author": [ { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Gatley", "given_name": "I.", "clpid": "Gatley-I" }, { "family_name": "Matthews", "given_name": "K.", "clpid": "Matthews-K" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Sellgren", "given_name": "K.", "clpid": "Sellgren-K" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Wynn-Williams", "given_name": "C. G.", "clpid": "Wynn-Williams-C-G" } ], "abstract": "The face-on Scd galaxy IC 342 has been studied at infrared wavelengths between 1.2 \u03bcm and 250 \u03bcm and at centimeter radio wavelengths. At 10 \u03bcm the nucleus is bright and extended on a scale of 200 pc, with a double structure unlike that of the stars seen at 2 \u03bcm. The infrared emission between 8 and 250 \u03bcm probably arises from heated dust grains in star formation regions in the disk of the galaxy. The radio emission comes from a region with many of the same spatial features as the 10 \u03bcm source; it appears to include both thermal and nonthermal sources. IC 342 is intermediate in luminosity between the Galaxy and NGC 253; the difference can probably be accounted for by a difference in the current rate of star formation at their centers.", "doi": "10.1086/157760", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "1980-03-01", "volume": "236", "pages": "441-447" }, { "id": "authors:bj5e3-hfv67", "collection": "authors", "collection_id": "bj5e3-hfv67", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200721-073121528", "type": "article", "title": "An infrared study of the NGC 7538 region", "author": [ { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Gatley", "given_name": "I.", "clpid": "Gatley-I" }, { "family_name": "Matthews", "given_name": "K.", "clpid": "Matthews-Keith-Astronomy" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Wynn-Williams", "given_name": "C. G.", "clpid": "Wynn-Williams-C-G" } ], "abstract": "Infrared observations of the NGC 7538 region at wavelengths from 1 \u03bcm to 1 mm are presented and analysed with the aim of understanding both the large-scale structure of this region of current star formation and the properties of the individual compact objects within it. At far-infrared wavelengths (25\u2013130 \u03bcm), emission is seen from the visible H II region, from the vicinity of the previously known maser sources and dust-embedded compact H II regions, and from a new region called NGC 7538(E). Coincident with NGC 7538(E) are a point-like 1\u201325 \u03bcm infrared source, NGC 7538-IRS9, which probably provides the power for the far-infrared emission, and an extended source of 2.2 \u03bcm emission which appears to be an infrared reflection nebula. NGC 7538-IRS9 strongly resembles the compact H II region NGC 7538-IRS1 in its infrared properties but shows no radio continuum emission. The compact H II regions, the maser sources and IRS9 are located within a dense molecular cloud at the edge of the optical H II region. This cloud, which has M\u223c9\u00d710\u00b3M\u2299, is detected in emission at 1 mm. The NGC 7538 region appears to contain examples of different stages in the formation of massive stars; it is suggested that the centre of star formation is moving systematically to the south-east in this region.", "doi": "10.1093/mnras/188.3.463", "issn": "0035-8711", "publisher": "Royal Astronomical Society", "publication": "Monthly Notices of the Royal Astronomical Society", "publication_date": "1979-10-01", "series_number": "3", "volume": "188", "issue": "3", "pages": "463-479" }, { "id": "authors:erkvr-jv487", "collection": "authors", "collection_id": "erkvr-jv487", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170303-153447009", "type": "article", "title": "The detection of the J = 3-2 lines of HCN, HNC, and HCO^+ in the Orion molecular cloud", "author": [ { "family_name": "Huggins", "given_name": "P. J.", "clpid": "Huggins-P-J" }, { "family_name": "Phillips", "given_name": "T. G.", "clpid": "Phillips-T-G" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Wannier", "given_name": "P. G.", "clpid": "Wannier-P-G" }, { "family_name": "Ennis", "given_name": "D.", "clpid": "Ennis-D" } ], "abstract": "We report the first measurements of the 1.1 mm (J = 3-2) lines of HCN, HNC, and HCO^+ in the Orion molecular cloud. The low-intensity broad velocity wings seen in the (1-0) lines of HCN and HCO^+ are greatly enhanced in the HCN (3-2) line but not in HCO^+ (3-2). No broad wings are seen in the HNC (3-2) line. The HCN observations suggest molecular hydrogen densities ~ 10^6 cm^(-3) in the broad wing source, and the differences between the lines of HCN and HCO^+ suggest that the lines may be formed in different regions within the source.", "doi": "10.1086/156750", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "1979-01-15", "volume": "227", "pages": "441-445" }, { "id": "authors:6x16b-f2436", "collection": "authors", "collection_id": "6x16b-f2436", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170303-153445815", "type": "article", "title": "Detection of submillimeter (870-\u00b5m) CO emission from the Orion molecular cloud", "author": [ { "family_name": "Phillips", "given_name": "T. G.", "clpid": "Phillips-T-G" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Huggins", "given_name": "P. J.", "clpid": "Huggins-P-J" } ], "abstract": "We report the first measurements of the interstellar J = 3 to J = 2 carbon monoxide line at a wavelength of 870 \u03bcm (346 GHz). Observations of the Orion molecular cloud were made with a heterodyne bolometer receiver at the prime focus of the Hale 5 m telescope. A major feature of the\nobserved spectra is the great strength of the high-velocity wings of the line. The position and spatial extent of the region of high-velocity emission are determined and compared with shock wave models for CO and H_2 emission. It is concluded that the high-velocity gas is probably at or near the front face of the molecular cloud and has a kinetic temperature \u2273 100 K a mass \u2273 10 M_\u2609 and a density n_H, \u2273 5 X 10^5 cm^(-3).", "doi": "10.1086/182561", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "1977-11-01", "series_number": "1", "volume": "217", "issue": "1", "pages": "L161-L164" }, { "id": "authors:7mpk6-s1e95", "collection": "authors", "collection_id": "7mpk6-s1e95", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151117-080411276", "type": "article", "title": "Infrared Studies of Star Formation", "author": [ { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" }, { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" } ], "abstract": "The lifetime of a massive star before it begins to deplete its nuclear fuel is less than 5 million years (1). In contrast, the age of the galaxy is more than 10 billion\nyears (2); nevertheless, many massive and short-lived stars have been identified by observations at optical wavelengths.\nThese massive stars must have formed very recently relative to the age of the galaxy, and therefore star formation\nmust be occurring in the galaxy at the present time.", "doi": "10.1126/science.197.4305.723", "issn": "0036-8075", "publisher": "American Association for the Advancement of Science", "publication": "Science", "publication_date": "1977-08-19", "series_number": "4305", "volume": "197", "issue": "4305", "pages": "723-732" }, { "id": "authors:0rca5-4kw81", "collection": "authors", "collection_id": "0rca5-4kw81", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200721-103531531", "type": "article", "title": "Infrared studies of H II regions and dust clouds near K3 - 50", "author": [ { "family_name": "Wynn-Williams", "given_name": "C. G.", "clpid": "Wynn-Williams-C-G" }, { "family_name": "Becklin", "given_name": "E. E.", "clpid": "Becklin-E-E" }, { "family_name": "Matthews", "given_name": "K.", "clpid": "Matthews-Keith-Astronomy" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" } ], "abstract": "New ground-based infrared observations of the K3\u201350 region are reported at wavelengths between 2 and 34 \u03bcm, and at 1 mm. The main results are (a) that the visible nebula K3\u201350 is displaced from its infrared and radio counterparts, (b) that component C1 (the OH source ON-3) appears very faint at \u03bb \u2a7d 20\u03bcm\u2060, and is therefore probably obscured by several hundred magnitudes of visual extinction, (c) that both K3\u201350 and component Care associated with separate condensations of molecular hydrogen, each of about 3000 M\u2299, and (d) there are no strong sources in this region at 20 \u03bcm other than those associated with H II condensations.", "doi": "10.1093/mnras/179.2.255", "issn": "0035-8711", "publisher": "Royal Astronomical Society", "publication": "Monthly Notices of the Royal Astronomical Society", "publication_date": "1977-06-01", "series_number": "2", "volume": "179", "issue": "2", "pages": "255-264" }, { "id": "authors:g92a9-yew70", "collection": "authors", "collection_id": "g92a9-yew70", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170303-153446123", "type": "article", "title": "Far-infrared observations of IRC + 10216", "author": [ { "family_name": "Campbell", "given_name": "M. P.", "clpid": "Campbell-M-P" }, { "family_name": "Harvey", "given_name": "P. M.", "clpid": "Harvey-P-M" }, { "family_name": "Hoffmann", "given_name": "W. F.", "clpid": "Hoffmann-W-F" }, { "family_name": "Elias", "given_name": "J. H.", "clpid": "Elias-J-H" }, { "family_name": "Neugebauer", "given_name": "G.", "clpid": "Neugebauer-G" }, { "family_name": "Gezari", "given_name": "D. Y.", "clpid": "Gezari-D-Y" }, { "family_name": "Westbrook", "given_name": "W. E.", "clpid": "Westbrook-W-E" }, { "family_name": "Hudson", "given_name": "H. S.", "orcid": "0000-0001-5685-1283", "clpid": "Hudson-H-S" }, { "family_name": "Soifer", "given_name": "B. T.", "orcid": "0000-0002-8112-1132", "clpid": "Soifer-B-T" }, { "family_name": "Werner", "given_name": "M. W.", "clpid": "Werner-M-W" } ], "abstract": "Broad-band photometric observations of IRC + 10216 in five wavelength intervals from 50 to 1000 \u03bc are reported. The observed radiation is interpreted as thermal emission from dust in the extended molecular cloud heated by the compact 2-20 \u03bc source as the core of the cloud. The shape of the 50-1000 \u03bc spectrum suggests that the emissivity of the dust particles varies approximately as \u03bb^(-1) over this spectral interval. The mass of dust inferred from the far-infrared emission is comparable with the mass of heavy molecules in the cloud.", "doi": "10.1086/154619", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "1976-09-01", "series_number": "1", "volume": "208", "issue": "1", "pages": "396-398" } ]